What size can of enchilada sauce?

Other similar recipes to make 6 to 8 servings of chile relleno casserole use between 10 oz and 3 cups canned enchilada sauce.
Since this recipe is for 4, use half that range. Start with the smaller amount and adjust as needed - to taste, or as it bakes depending on how much you like your casseroles drier or with more liquid.
If you have leftover sauce from one of your 28 oz cans, you can freeze it up to 3 months.
https://carlsbadcravings.com/enchilada-sauce/#:~:text=To%20freeze%20Enchilada%20Sauce%3A&text=Transfer%20to%20freezer%20safe%20glass,broth%20to%20reach%20desired%20consistency.