Chocolate Chip Crunch Cookies

Got this one at a recent cookie exchange.

• Ready In: 35 mins
• Yields: 16 cookies

Ingredients

• 1⁄4 cup unsalted butter, softened
• 1⁄3 cup  firmly packed light brown sugar
• 1  large  egg yolk, plus
• 2  teaspoons water or 1  large  egg white
• 1⁄2 cup all-purpose flour
• 1⁄4 teaspoon double-acting baking powder
• 1⁄4 teaspoon salt
• 1⁄4 teaspoon vanilla
• 1  cup  semi-sweet chocolate chips
• 1⁄2 cup  toasted rice cereal

Directions

1. Preheat the oven to 375°F In a bowl with an electric mixer cream the butter with the brown sugar until the mixture is light and fluffy and beat in the egg yolk mixture or the egg white.
2. Add the flour, the baking powder, the salt, and the vanilla, stirring until the dough is blended well, and stir in the chips and the cereal.
3. Arrange level tablespoons of the dough 2 inches apart on a lightly greased baking sheet and bake the cookies in the middle of the oven for 8 to 10 minutes, or until they are golden.
4. Transfer the cookies with a spatula to a rack and let them cool.