According to my research, Mexican Basil is Cinnamon Basil.

"This is a tall, vigorous, bushy variety with thick, glossy, dark green leaves with a strong, spicy, cinnamon-like scent and flavour. Dried, the fragrance keeps for months and makes a good tea. Ideal for Mexican cuisine."

Here is a link that might be useful: cinnamon basil recipes

Soil conditions, as well as other growing conditions can make the flavor different. I never buy herbs or any other plants except a few flowers from places like Home Depot. My last experience was supposed to be brussles sprouts, but the plants produced cabbages instead. Clearly not the same, even though they may look similar at a very young sage. For herbs that you need specific types, suggest that you buy seeds instead, and grow your own plants.

Seeds, agreed.

Or buy plants from reputable locally owned and operated nurseries or mail-order from specialty nurseries for the uncommon stuff. Some plants are difficult to grow from seed or are not true from seed like peppermint and tarragon.

FataMorgana

Oops! I think I'm in the same boat. My neighbor gave me some "Mexican Basil." Like you I just assumed that it was Thai Basil.

But my neighbor makes pesto with it...and it's good pesto. I've put a few leaves in a green salad. I've made a cold soup (tomatoes, bell pepper, onion, garlic, salt, pepper and tomato juice and threw in a little chopped Mexican Basil instead of cilantro. We thought it was delicious. It's a bit strong though isn't it.

Wow!.....I was jus' told about this Mexican Basil and it's medicinal properties!