Abrikozenkoekjes

Leaking almost always means the dough was not fully sealed around the filling. After adding the dollop of jam, pinch the dough closed completely and place the ball with the sealed side facing down so any weak spot is pressed against the baking sheet. Use only a small dollop - overfilling makes the seam split as the jam heats and expands.

Yes, any thick jam works in place of the apricot - the recipe only asks for a small dollop enclosed in the dough. Choose a firm, set jam rather than a runny fruit spread or jelly, since a thin filling flows more easily through any gap in the seam. Very chunky preserves are harder to seal, so press larger fruit pieces out or chop them first.

Usually the butter was too cold, so it never creamed properly with the powdered sugar. The recipe calls for room-temperature butter for exactly this reason: it has to whip smooth before the egg yolk goes in. If the dough still crumbles when you shape the 25 g balls, knead it briefly with your hands - the warmth is often enough to bring it together.

Yes, the dough can be made in advance and kept chilled until you are ready to shape it. Let it sit at room temperature until it is pliable again before rolling the balls, otherwise cold dough cracks when you press the well into the center. You can also shape and fill the balls ahead and bake them straight from chilled, adding a minute or two if needed.

Keep them in an airtight container at room temperature - they are a butter-rich shortbread-style cookie and stay tender for days. Make sure they have cooled completely before storing, as the recipe directs, since trapped warmth creates condensation and softens them. Dust with powdered sugar just before serving if you want the coating to stay bright, because the sugar slowly dissolves into the cookie in storage.