Hi Tess, A couple tips to help you get thick cookies, did you make sure to use cold butter cut into sliced and mixed into the dough cold? Second, the higher temperature actually helps the cookies to spread less because it cooks the tops faster and they hold their shape better. Third, the size of your cookie dough balls will also affect how much your cookie dough spreads. (If your cookies are turning to dark quickly with the 400 temp, are you baking on the middle rack? Maybe you’ll want to bake on the bottom rack)

Lastly, I usually do add extras on my cookie dough balls, but these cookies are super loaded as is, and I haven’t felt the need with this recipe. Did you add the full 1.5 cups of pretzels and chocolate chips to the cookie dough (that will ALSO help them hold their shape) Sorry for all the info! I’ve made these several times with success, so hopefully I can help you!