Cook pasta al dente, according to package directions.
Preheat oven to 375 degrees F.
Dice onion finely, and mince garlic.
Heat 1 tablespoon olive oil over medium heat in a large sauce pan or dutch oven. Add onion and garlic and saute for a few minutes until the onion is translucent.
Add the pumpkin puree and plain yogurt, stir until smooth, cooking for a minute.
Turn the heat down to medium low. Pour in the chicken broth and paprika, stir until smooth, cooking for 3-5 minutes.
Shred both kinds of cheese, and keep separate.
In a bowl, toss the flour and the Gouda cheese together. Then add in all of the Gouda cheese to the sauce. Reserve the 1/2 cup sharp for later. Stir until melted.
Season with salt and pepper to taste.
Add cooked pasta to sauce, tossing gently to combine. Spoon into a baking dish.
Top the pasta with the remaining cheddar cheese, and breadcrumbs. Bake for 12-15 minutes and serve.