I'm basing it on personal experience, with grandparents and further back recipes.

I don't think something like avocados even existed here, or any type of spicy pepper.

I'm a spicehead, and nothing has any at all. Or much say, umami. Meat and potatoes. Meat and green beans. Add salt or bland spice, if you're lucky. It's basically all I ate growing up.

Today I can buy Nashville hot spice in a can, for example.

I'm sure you can find examples of some things existing in some places. But the silk road didn't run through rural midwest.

Edit to add: Speaking of avocados, and complex favors...imagine a perfect guacamole. With avocados, and spicy peppers, garlic, onion, etc. Does a recipe exist for such a thing before say, 1960?