Preheat the oven to 350 F. Cook pasta according to package directions, drain. In a large saucepan over medium heat, melt butter. Add in flour and ranch seasoning mix. Cook for a minute to brown.
Add in the milk and cheese, cook until the cheese has fully melted, and the sauce has thickened. Mix the sauce with the pasta. Separate the biscuit dough, and place one in a greased muffin pan. Fill each biscuit with the mac and cheese.
Top with the fried onions. Bake for 12-15 minutes.