Melt butter. In a heavy-based saucepan, melt butter slowly, then when completely liquid, raise heat and allow to froth, stirring constantly. As froth subsides, butter will begin to stick to pan, creating a brownish substance on surface of the pan. This is good. The butter should now have a butty aroma. Once the butter has browned, take off heat immediately, before it burns. Set aside to cool slightly.