Beat the butter, sugar and a pinch of salt until light and fluffy. Add the flour, lemon zest and vanilla. Cover the bowl with plastic wrap and rest for half an hour. Preheat the oven to 356 degrees F (180 degrees C). Cover a baking sheet with parchment paper. When the dough is done resting, press the dough into a rough square shape on the parchment paper with the palms of your hands. It needs to be roughly a 1/2 inch thick (1 cm). Bake for 10 to 15 minutes or until the top goes slighlty brown. (Be careful, it burns quickly!) Remove from the oven, immediately cut into squares, and allow to cool on the baking sheet.Makes about 25 pieces.

TIPS

Butter biscuits are usually made in a special round boterkoek tin. The butter biscuits are then cut into wedges, leaving them somewhere between a cake and a cookie. But, because I don’t expect anyone outside of Holland to be able to track down one of these specialty tins, I’ve kept it simple. As suggested above, bake them on a baking sheet and cut into squares. Or, if you want, form a rough round circle shape and cut into wedges. It’s up to you.

source: http://dutchfood.about.com