Like pancakes crossed with Yorkshire puddings, puffy and light Danish aebleskiver are cooked on the stove top in a special pan with hemispherical hollows. You need to get the pan hot, but not too hot, otherwise the spheres will cook on the outside, but not on the inside.
First, make the spiced apple filling. Tip the diced apples into a pan with the butter, lemon juice, salt, sugar, nutmeg and cinnamon. Cook over a medium heat until the butter has melted, then reduce the heat to low and simmer for 20–25 minutes, until the apple is tender, but still holding its shape. If the apple gets too dry during cooking, add a splash of water.
Sift the cornflour over the apple and cook for 2–3 minutes, until the apple mixture has thickened. Remove from the heat and leave to cool completely.
Meanwhile, make the strawberry dipping jam. Tip the strawberries into a pan with the jam sugar. Bring to the boil, crushing the strawberries with a potato masher. Boil until the temperature on a sugar thermometer reaches 102°C/216°F, then remove from the heat and press through a metal sieve, to remove the pips. Add a knob of butter to the strawberry purée to disperse any scum, then leave to cool to a warm, runny jam.
Make the batter. Whisk the egg white and sugar together until fluffy and stiff, but not dry. Set aside.
Sift the flour, salt and bicarbonate of soda into a bowl and make a well in the centre. Mix the buttermilk and egg yolk together in a jug. Melt the butter in a small pan and set aside to cool slightly.
Using a handheld electric whisk, gradually pour the buttermilk mixture into the well of the dry ingredients, whisking continuously to a smooth batter.
Slowly whisk in the melted butter, then carefully fold in the egg white mixture.
Heat the aebleskiver pan over a medium–high heat. Dot a little knob of cold butter into each of the 7 holes to grease. When melted, spoon the batter into the holes until they are ¾ full, then reduce the heat to medium and cook for 1–2 minutes, until the edges begin to firm.
When the edges are firm, turn the aebleskiver through 90 degrees using 2 wooden skewers, allowing the batter to flow into the pan. It’s as though you were turning the aebelskiver over in the hollows, but you stop once you get to a quarter turn.
At this point there is a hole in the side of the aebleskiver. Spoon a little of the spiced apple mixture into the hole and turn the aebleskiver another 90 degrees to close. Cook for 3–4 minutes, until firm.
When the aebleskiver are firm, turn them regularly for about 4–5 minutes more, until they have an even and golden-brown crust. Remove from the pan and serve dusted with icing sugar.