Prepare a 9x13 casserole. Put bagel pieces on the pan evenly.Crumble Italian sausage in a pan over medium heat until no longer pink. Mix sausage evenly into bagel pieces.
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Step 1
Mix eggs, milk, salt, pepper, garlic, mustard, basil, and chives in a large bowl. Put mixture on bagels. Wrap in foil and chill 2 hours or overnight.
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Step 2
Let the dish come to room temperature while the oven preheats to 375 degrees.
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Step 3
Remove foil after 35 minutes, sprinkle with cheese, and bake for 10-15 minutes until top is browned and cheese melts. Wait 10 minutes before adding fresh chives and serving.