You can substitute brown butter for melted butter in most recipes. But be aware that there is a loss of moisture in the browning process, so you’ll want to measure the brown butter after making it. For example - you will likely need to brown 9 tablespoons of butter to get 8 tablespoons of browned butter. If the recipe calls for cold butter or even room temperature, softened butter then substituting brown butter will not be an even 1:1 swap and recipe testing will be needed.