First, we'll crisp the Beddar with Cheddar sausage. Heat medium skillet on medium heat. Add a little nonstick spray. Add sliced Beddar with Cheddar sausage to pan and cook until the bottom gets brown and crispy, about 4 minutes. Flip and cook the other side for another 3 minutes. Remove and set aside.
Place skillet back on heat. Add brat sausage meat (removed from casings) and break it up with a wooden spoon. Cook until the sausage is browned, about 5-7 minutes. Drain and set aside.
Place a large saucepan over medium-low heat. Add butter and let it melt completely. Once melted, add flour and whisk together to make a roux. Once flour and butter have combined, let it cook until it starts to turn golden brown, about 5 minutes. Slowly whisk in the half and half.
Let the milk mixture heat up until bubbles start to form around the edge. Reduce heat to low. Add about 1/4 cup of the shredded cheese to the mixture and whisky continuously until it completely melts. Repeat with rest of cheese in 1/4-cup increments. Do NOT add more than 1/4 cup of cheese at a time. Otherwise, the cheese will clump up and remain lumpy.
Once the cheese is completely smooth and melted, add diced chiles, tomatoes, spices, and garlic. Whisk together. Then, add in the sliced cheddar sausage and crumbled brat sausage. Stir together with a wooden spoon. Raise heat back to medium to get the cheese nice and hot. Continue stirring until cheese is hot.
Give cheese a taste. Add salt and pepper, if necessary. Place cheese into a large skillet or other serving dish. Serve with a bowl of tortilla chips and ice-cold Dr Pepper!