Bolas de Berlim

Step 1: Mix 1 ⅛ lb strong white bread flour, ¼ oz fast-action dried yeast, 2 ⅛ oz caster sugar, 1 tsp salt and 1 lemon in a large bowl. Add ¾ cup whole milk and 2 eggs and mix to a shaggy dough.

Step 2: Knead for 8 minutes by hand (5 in a mixer), then work in 2 ⅛ oz unsalted butter a little at a time and knead until the dough is smooth, glossy and stretches thin without tearing.

Step 3: Cover and leave somewhere warm until doubled in size.

Step 4: Meanwhile make the custard: heat 2 cups whole milk with 1 strip unwaxed lemon peel until steaming. In a bowl whisk 4 egg yolks, 3 ½ oz caster sugar and 1 ⅜ oz cornflour to a smooth paste.

Step 5: Remove the peel and pour the hot milk onto the yolks in a thin stream, whisking. Return to the pan over a medium heat and whisk constantly until it bubbles and turns very thick, then cook 1 minute more so it doesn't taste floury.

Step 6: Scrape into a bowl, press cling film onto the surface and chill until cold and firm.

Step 7: Knock back the dough and divide into 12 pieces (about 75 g each). Roll each into a tight, smooth ball and set on squares of baking paper on a tray, spaced well apart. Flatten each slightly.

Step 8: Cover loosely and leave until puffy and nearly doubled.

Step 9: Heat 6 ¼ cups sunflower oil in a deep, heavy pan to 165–350°F. The common mistake is frying too hot: the outside goes dark brown before the middle cooks. Use a thermometer and keep it steady.

Step 10: Lower 3 balls at a time into the oil on their paper squares (pull the paper out with tongs after a few seconds). Fry until deep golden with a pale ring around the middle, turning once.

Step 11: Drain on kitchen paper for 1 minute, then roll in 5 ½ oz granulated sugar while still warm. Fry the rest, checking the oil temperature between batches.

Step 12: When cool, cut each ball deeply along one side without going all the way through. Beat the cold custard smooth, spoon it into a piping bag and fill each one generously. Eat the same day.