complementary cheeses

Everyone knows that mozzarella and parmesan go together, but what about other cheese pairings? For example, if I put extra sharp cheddar in a casserole and want to use a cheese sauce over it, what works well besides more cheddar? It makes sense that a cook would not use two strong cheeses, but what can “bring out” or complement each part of a dish?

Thank you in advance for your ideas.

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