Mantelipurilaiset

Lumps usually mean the cornstarch slurry hit the hot milk unevenly. Always stir the cornstarch, sugar, egg yolk and the 3 tbsp reserved cold milk into a completely smooth paste before whisking it into the hot milk, and keep whisking constantly while it comes to a gentle boil. If lumps still form, push the hot cream through a fine sieve right away, then stir in the butter.

Ground blanched almonds keep the cream pale and mild; almonds ground with the skins on work too but will speckle the filling and taste more rustic. The recipe already treats puff pastry and Danish pastry as interchangeable - Danish pastry bakes up a little softer and sweeter, puff pastry crisper and flakier. For the flaked almonds on top you can substitute chopped almonds; scatter them thinly so they toast rather than burn at 200 °C.

The almond cream is the ideal make-ahead component: cook it, cool it, and keep it covered in the fridge, then fold in the heavy cream and whip it briefly just before piping. The pastry rounds can be baked a few hours in advance and left uncovered at room temperature so they stay crisp. Only assemble and dust with powdered sugar shortly before serving.

Once filled they contain a dairy-based cream, so keep them refrigerated and eat them the same day. The pastry softens where it meets the cream, so the texture is best within a couple of hours of assembly. Leftover cream on its own keeps covered in the fridge; re-whip it briefly if it firms up.

Cut the circles with a firm downward press rather than twisting the cutter - twisting seals the layered edges and stops the pastry rising evenly. Make sure the moistened, folded double layer is pressed together well so the two sheets bake as one, and brush the egg yolk - milk mixture on the top only, not down the cut sides. If they are still pale after 12 minutes, give them the full 15 until deep golden; underbaked pastry collapses once the cream goes in.