Heat a large nonstick skillet over medium high heat. Season chicken with salt, pepper, paprika and chili powder. Drizzle breast with a little extra virgin olive oil to coat. Pan grill chicken breasts 5 minutes on each side.
Heat a metal or oven safe glass bowl over low heat and melt butter in the bowl. Add hot sauce to the butter and combine. When the chicken breasts are done, remove from pan and add to the bowl and coat evenly with hot sauce mixture.
Place chicken breasts on bun bottoms and top with crisp lettuce. Combine sour cream, scallions and blue cheese and slather bun tops with blue cheese sour cream. Affix bun tops on sandwiches and serve with remaining sauce for dipping your veggies. Arrange Buffalo Chicken Sandwiches on dinner plates with red onion, celery and carrot sticks.