Onion butter is a versatile condiment that can be used in a variety of dishes, from sauteed vegetables to grilled meats. If you're looking to mix up your flavor profiles, consider using some synonyms for onion butter. One option is to use caramelized onion jam, which can lend a slightly sweeter flavor to your dishes. Another choice is to try using shallot butter, which has a slightly milder and more delicate flavor than onion butter. You could also try using garlic butter for a more pronounced herbaceous flavor, or chive butter for a subtler onion flavor with a bright pop of green. Ultimately, the choice is up to you - experiment and find the flavor profile that best suits your palate and culinary needs.