This recipe is different from the other cinnamon toast recipes that I have seen on this site. You start off making a brown sugar/cinnamon and butter mixture and then the toast is briefly broiled. From the Best of the Best from Ohio Cookbook.
In a small mixing bowl, cream together butter and brown sugar until light and fluffy. Beat in milk, cinnamon and salt. Spread entire top of lightly toasted bread with butter mixture. Place on a cookie sheet and broil briefly until mixture bubbles. (Watch carefully as these will burn quickly.) Cool slightly on a rack; cut into triangles, and serve warm for breakfast toast. Cover and refrigerate remaining butter mixture for future use.