THE RESULT: Tough cookies, scones, piecrusts, and biscuits.THE FIX: Recipes with lots of butter are more likely to stay moist and tender because of the fat, even if the dough is overmixed and overkneaded. But in light baking, you absolutely must use a light hand. Vigorous mixing encourages gluten development, which creates a chewy or tough texture—great in a baguette but not in a biscuit. That’s why many of our biscuit and scone recipes instruct the cook to knead the dough gently or pat it out instead of rolling, and our cookie and piecrust recipes say to mix just until the flour is incorporated. To be safe, stop machine-mixing early and finish the last bit by hand. It really does make a difference.