Slow-cooker mains
Top 10 Flank Steak Recipes
Most of the removable crockpot inserts can be used in an oven. The upper temperature limit varies by the manufacturer though, and you would want to check with whoever made yours. If it is a name brand Crockpot, the insert is safe up to 400F. I know this because I own one of these, and that's what the package insert says, as well as their site.