I never know what to do with leftovers after I fix a pot roast with gravy, onion, potatoes and carrots until I found this recipe. I wouldn't really call it a strata because it doesn't have bread cubes in it. Rather, it has a yorkshire pudding baked around everything else. The recipe came from a book called "Marnie's Kitchen Shortcuts" by Marnie Swedberg. The recipe calls for specific amounts, although I tend to throw in whatever amount of leftovers I have.