Just trim it and dry it. It will crumble to small peaces later. And not sure what you mean by use same butter on maltiple batches. But here is what I do. Make 1 batch then use new trim and make another. Save all the butter chunks till all the butter is made. Use a double boiler to melt it all together mix and strain 1 last time with cheese cloth. Then in 1 cup storage containers gose the butter. All your butter is now the same. So after you cook your first batch is cookies/brownies or what ever you will know if you want to add more or less. Also when cooking you don't want to have it above 220 degrees.
