Why does my first cookies come out nice and later batches get thin?

Question

The first few batches that get backed look good and have a thickness to them. The last few batches are thinner. Why would that happen? I follow the nestle tollhouse chocolate chip recipe.

Answer

The fat in your dough started to soften/melt - especially if you have a hot oven running in the kitchen. Keep your dough cold in the fridge between batches.

See this question for more details on the issue in general, but for your situation, keep it cold between batches. You seem to have started correctly, which is good - you just have to keep it going right.

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