Crushed tomatoes, tomato sauce, or fresh tomatoes can be used as substitutes for diced tomatoes in a recipe.
You can use canned diced tomatoes or cherry tomatoes as a substitute for plum tomatoes in a recipe.
Fresh tomatoes, tomato sauce, tomato paste, or diced tomatoes can be used as substitutes for canned tomatoes in a recipe.
Green tomatoes can be used as a substitute for tomatillos in a recipe.
Tomato paste, tomato sauce, or diced tomatoes can be used as substitutes for tomato extract in recipes.
Pickles or gherkins can be used as a substitute for cornichons in a recipe.
Gelatin can be used as a substitute for agar powder in a recipe.
Butter or margarine can be used as a substitute for shortening in a recipe.
Artichoke hearts can be used as a substitute for hearts of palm in a recipe.
Basil leaves can be used as a substitute for shiso leaves in a recipe.
A substitute for red bell pepper in a recipe can be using green bell pepper, yellow bell pepper, or even a combination of other colorful vegetables like tomatoes or carrots for a similar flavor and texture.
Cremini or button mushrooms can be used as a substitute for chestnut mushrooms in a recipe.
Ground sassafras leaves can be used as a substitute for gumbo file in a recipe.