Preheat oven 160 C. Brush cookie sheet with margarine, sprinkle with flour. Beat margarine until creamy, beat in yolks, continue beating until fluffy.
Add in grated edam and flour, stir to combine.
Roll dough into 1/2 cm thickness, brush surface with yolk
Sprinkle grated cheddar all over and slice dough into 1×4 cm sticks
Move cookies onto cookie sheet and bake for 30 mins. Take out sheet from oven, let cook slightly before moving cookies to cooling rack.