Pineapple Upside-Down Brownie — caramelised pineapple over fudgy chocolate

i. Origin & history

Upside-down cakes are older than the pineapple version. Cooks long baked cakes in cast-iron skillets over fruit and sugar, then flipped them out — the same principle as the French tarte Tatin. What made the pineapple upside-down cake a national favourite in the United States was canned pineapple. In the early twentieth century, James Dole's Hawaiian Pineapple Company and its competitors began canning pineapple in uniform rings, cut by machine, and promoted them heavily to American home cooks.

Recipes for pineapple upside-down cake appear in American newspapers and cookbooks from the 1920s. The story often told is that a 1925 recipe contest run by the Hawaiian Pineapple Company received thousands of upside-down cake entries, prompting the company to publicise the recipe further; whether or not the numbers are exact, by the 1930s the cake — rings, a cherry in each hole, a brown-sugar glaze — had become a standard of American baking.

The brownie is roughly contemporary: chocolate brownies are usually traced to the 1890s–1900s, with the Palmer House Hotel in Chicago often credited with an early version and printed recipes appearing in American cookbooks from the 1900s onwards. It became the country's favourite bar cookie.

The pineapple upside-down brownie is a modern combination of the two, part of a wave of 'mash-up' desserts that spread through food blogs and social media in the 2010s. It has no single inventor. It is especially popular for potlucks and summer parties, where it travels in its tin and makes an impression when turned out.

ii. Keeping the fruit layer from making the brownie soggy

The topping and the brownie want different things. The pineapple layer is wet: tinned pineapple carries a lot of syrup, and as it bakes it releases juice into the butter and sugar to make a caramel. A brownie, by contrast, is a low-moisture, high-fat batter that should bake to a dense, fudgy set. Left uncontrolled, the pineapple juice soaks upward into the brownie and leaves a pale, gummy layer just above the fruit.

The first defence is to dry the fruit. Draining the rings and patting them firmly with kitchen paper removes the surface syrup, so the liquid in the tin is mostly butter and sugar, which cook into a thick caramel rather than a thin syrup. The second is to cook the caramel briefly before adding the fruit: melting the butter and brown sugar together and letting them bubble for a minute gives a sauce that sets glossy and holds the rings in place when the brownie is inverted.

The brownie batter itself is slightly firmer than a standalone brownie — a little more flour and eggs — because it has to support itself when turned out and must set above a moist layer. It also needs longer in the oven than an ordinary brownie, since the fruit layer slows the heat reaching the bottom of the tin. The test is the same: a skewer in the centre should come out with moist crumbs, not wet batter.

Finally, timing the flip matters. Turn the brownie out after about 10 minutes. Too soon and the caramel is liquid and runs everywhere; too late and it sets hard, gluing the fruit to the tin. Lining the tin with baking paper insures against both.

iii. Ingredients

Makes 16 servings · scroll the side panel to adjust

• 60 g unsalted butter, for the topping
• 100 g light muscovado or soft brown sugar
• 9 tinned pineapple rings in juice, drained and patted dry
• 9 maraschino or glacé cherries
• 200 g dark chocolate (60–70% cocoa), chopped
• 150 g unsalted butter, for the brownie
• 250 g caster sugar
• 3 large eggs
• 1 tsp vanilla extract
• 110 g plain flour
• 25 g cocoa powder
• ½ tsp fine salt

Tinned pineapple in juice is the standard and gives even rings; fresh pineapple works if cut into 1 cm slices and cored, and has a brighter flavour. Muscovado gives a deeper, toffee-like caramel than white sugar, which is what makes it read as 'upside-down cake'. Use a good dark chocolate of 60–70% — very bitter chocolate fights the fruit, while milk chocolate makes the whole thing cloying. Maraschino cherries are traditional for their colour; glacé cherries or fresh pitted cherries are fine. A spoonful of dark rum or the zest of a lime in the caramel is a good addition.

iv. Method

1. Heat the oven to 170 °C (340 °F), or 150 °C fan. Line the base and sides of a 23 cm square tin with baking paper.
2. Melt the 60 g butter and muscovado in a small pan and let it bubble for 1 minute, stirring, until smooth and syrupy. Pour into the tin and tilt to cover the base evenly.
3. Arrange the dried pineapple rings in three rows of three on the caramel, trimming any that overlap, and press a cherry into the centre of each.
4. Melt the chocolate and 150 g butter together in a bowl over barely simmering water, or in short bursts in the microwave, until smooth. Cool for 5 minutes.
5. Whisk the caster sugar, eggs and vanilla for 2–3 minutes until pale and slightly thickened, then whisk in the chocolate mixture. Sift in the flour, cocoa and salt and fold until no streaks remain.
6. Spoon the batter gently over the pineapple, starting at the edges so the fruit does not shift, and smooth the top.
7. Bake for 40–45 minutes, until the top is set with a papery crust and a skewer in the centre comes out with moist crumbs but no wet batter.
8. Cool in the tin for 10 minutes. Run a knife round the edge, place a board or tray over the tin and invert in one confident movement. Peel off the paper, nudging back any fruit that has moved, and leave to cool completely before cutting into 16 squares.

v. Tips & common mistakes

• Pat the pineapple dry. Syrupy fruit thins the caramel and soaks the bottom of the brownie, leaving a gummy layer.
• Bubble the butter and sugar first. A cooked caramel sets glossy and holds the fruit; raw butter and sugar can stay gritty.
• Line the tin with paper. Caramel sets like glue on bare metal. Paper guarantees a clean release.
• Bake longer than a plain brownie. The wet fruit layer slows the bake; check from 40 minutes and expect up to 45.
• Flip after 10 minutes. Earlier and the caramel floods; later and it hardens and tears the fruit away from the brownie.
• Cut with a hot knife. Dip it in hot water and wipe between cuts, cutting between the rings so each square shows fruit.

vi. Variations

The classic pineapple upside-down cake uses a butter sponge instead of brownie. A blondie version uses brown butter and white chocolate, which lets the pineapple's acidity show more; desiccated coconut in the batter makes it tropical. Banana, peach or apricot slices can replace the pineapple, and a rum caramel nods to the Caribbean. For individual servings, bake in a muffin tin with half a ring in each hole for 25–30 minutes.

For more caramelised-fruit desserts, see New Orleans' flambéed bananas Foster, or try the Taiwanese pineapple cake, a buttery pastry filled with pineapple jam. Other American bar cakes include seven layer bars, and for pineapple and coconut in a pastry case, the pineapple coconut tart.

vii. Serving & storage

Serve at room temperature in squares, on its own or with vanilla ice cream, crème fraîche or lightly whipped cream; a scoop of coconut ice cream suits it particularly well. It can also be served slightly warm as a pudding, when the caramel is soft and saucy.

Keep covered at cool room temperature for 2–3 days; the fruit topping keeps the brownie moist. In warm weather, or for longer keeping, refrigerate for up to 5 days and bring back to room temperature before eating. The squares freeze well for up to 2 months, wrapped individually — thaw at room temperature. It can be baked a day ahead; the flavours settle and it slices more neatly on the second day.

ix. More from North American

• Seven Layer Bars — coconut and chocolate magic bars
• Blackout Cake — Brooklyn chocolate layer cake
• Bananas Foster — New Orleans rum-caramel bananas
• Pineapple Cake — Taiwanese pineapple pastry
• Pineapple Coconut Tart — tropical fruit tart
• Mexican Chocolate Cake — cinnamon-spiced chocolate