What is craquelin made of?

The dough is softened bits of butter, sugar, and flour. The dough will keep for up to two months in the freezer. In a bowl, cream together the butter and sugar with a sturdy spatula or wooden spoon, then add the flour and salt, and continue to mix the dough until it’s smooth. The topping is called craquelin, a simple dough that’s easily put together and is a nifty little trick to gussy up ordinary cream puffs. You can also use a stand mixer with the paddle attachment. Course Dessert Cuisine French Servings 50 cream puffs 3 ounces (85g) unsalted butter, cubed, at room temperature 1/2 cup (100g) packed light brown sugar 3/4 cup (100g) all-purpose flour Pinch of salt