Resistance is futile ;-)

Ah halving the recipe may be the problem because it is difficult to use half an egg. As for bake time, the cookies will seem underbaked after 10 minutes when you first take the out of the oven. I have to let my cookies cool for at least 10 minutes on the pan before carefully removing to a wire rack. Once the cool completely they will not be so gooey, but underbaking is key for chewy cookies.

Thanks for the reply! I halved the recipe and used 1/2 teaspoon. I baked mine for 12 mins though. I baked the first batch at 10mins and they didn’t puff up as much as the later batches, just that it was too undercooked so I had to increase the baking time. Does baking Too long make them puff up too? =\

Oh boo I am sorry to hear that! I hope they still tasted good. But so odd, I’ve made this cookie recipe many times and have yet to have that happen. The only thing I can think of is too much baking soda. Are you sure you used 1 tsp and not 1 Tbsp? Maybe I should start writing out teaspoon and Tablespoon to avoid potential confusion.