Cowboys and....cookies?

So, I must admit I got this recipe off of the "internet" from this website called "epicurious.com". If you haven't been there, you guys should check it out. Its pretty fantastic if you're into this whole cooking thing. (I hope you can detect the sarcasm, or else I just look like a jackass. anyway).

Cookies are my MO, and chocolate chip in particular. These are called Colorado Cowboy Cookies; I assume because they are supposed to be of colossal size. But, when I made them, they flattened out to about 1 cm thick and about 5 inches wide-I think they're supposed to be closer to 1/2 in. They were still delicious, as both I and Lisa can attest as we sit here painfully satiated. Anyway, if anyone has any suggestions on how to keep them thicker as they bake, please come forth with ideas. I also think these would be delicious with coconut...

This recipe makes about 20 ENORMOUS cookies:

2 cups all purpose flour
2 cups old-fashioned oats
1 teaspoon baking soda
1/2 teaspoon baking powder
1/2 teaspoon salt
1 cup (2 sticks) unsalted butter, room temperature
3/4 cup sugar
3/4 cup plus 2 tablespoons (packed) dark brown sugar
2 large eggs
1 teaspoon vanilla extract
1 1/2 cups semisweet chocolate chips--I think dark chocolate chucks of good baking chocolate would be even better
1 cup chopped toasted walnuts (about 4 ounces)

Whisk first 5 ingredients in medium bowl to blend. Using electric mixer, beat butter and both sugars in large bowl until light and fluffy. Add eggs and vanilla, beating to combine. Add dry ingredients and beat until just blended. Stir in chocolate chips and walnuts. Cover dough and chill 1 hour. (Can be made 1 day ahead. Keep chilled. Let soften slightly before continuing.)

Arrange 2 racks in center of oven; preheat to 350°F. Butter 2 baking sheets. Form dough into balls, using 1/4 cup dough for each. Place on prepared sheets, spacing 2 inches apart. Flatten with hand to 3 1/2-inch rounds. Bake 10 minutes, then rotate sheets. Bake until cookies are golden brown around edges and firm in center, about 4 minutes longer. Cool on sheet 5 minutes. Transfer to racks to cool completely.