Heat the butter in a small saucepan over medium heat and add the garlic. Simmer for 30 seconds, stirring constantly.
Add in the flour and cook, stirring 1-2 minutes, or until flour is cooked and lightly golden brown.
Whisk in the milk and reduce heat to medium-low. Let cook a few minutes, until lightly thickened and add in the bell pepper, nutritional yeast, cashews salt, cumin and chili powder. Cook for 5 minutes, stirring occasionally, until thickened.
Transfer to a blender and puree until creamy, or use an immersion blender and puree until creamy. Return back to the pot, then stir in the salsa. Taste, adding salt as needed. Also tastes great with a squirt of lime juice!