Sieve the flour into a mixing bowl and add the diced butter.

Rub the butter and flour with your fingertips until they become like fine breadcrumbs. You can also use a food processor if you want to do it quickly. But take care not to process it for too long. 

Add vanilla extract (if using) and quickly mix until the dough just comes together. Do not be tempted to knead it.

Preheat the oven at gas 4/ or 180° C/ 350° F temperature.

Prepare and line a few cookie baking trays.

Dust the work surface with a small amount of flour. Roll the dough into a 3 mm/ 0.12 inch thick. 

Using a 5 cm/ 2 inches in diameter round cookie cutter, cut the rolled dough into circles. 

Put about a teaspoon of pineapple jam onto each circle. And close and cover the jam with the pastry and roll it into a small round ball. Then place the ball dough on the tray.

Beat the other egg yolk and brush the cookie balls with this egg wash. 

Insert one clove in every cookie.

Bake for about 20 minutes or until the cookies are golden in colour.