Cook the bratwurst in a pan oven medium high heat until well browned, breaking up as it cooks. Add ¾ cup beer, allow to simmer as you prepare the cheese sauce.
Add the remaining ¾ cup beer, cream cheese, cheddar (reserve 1 cup for the top), smoked paprika, chili powder, garlic powder, and cornstarch to a blender, blend until smooth.
Add cheese sauce to the pan, stirring until well combined.
Pour into an 8x8 baking dish, top with remaining cheddar.
Bake at 350 until cheese is bubbly. Garnish with green onions prior to serving.