Heat 1 tablespoon olive oil in a large skillet or cast iron pan over medium heat. Add Italian sausage links spaced 1-inch apart. Cook for 4-5 minutes per side until golden brown and internal temperature reaches 160°F. Transfer sausages to a plate and tent with foil.
1.5 lbs Italian sausage links, 2 tbsp olive oil
Add remaining 1 tablespoon olive oil to the same pan. Add sliced bell peppers and onions. Sauté for 12-15 minutes, stirring every 2-3 minutes, until peppers soften and edges char. Season with salt, black pepper, dried oregano, and red pepper flakes if using.
3 large bell peppers, 2 medium onions, salt, black pepper, dried oregano or Italian seasoning, 0.25 tsp red pepper flakes, 2 tbsp olive oil
Push vegetables to sides of the pan. Add minced garlic to the center and cook for 1-2 minutes until fragrant, stirring constantly to prevent burning. Then mix garlic into vegetables.
4 cloves garlic
Pour ¼ cup water or white wine into the pan and scrape browned bits from the bottom with a wooden spoon. Slice rested sausages into 1-inch pieces and return to pan. Toss everything together and cook for 2-3 minutes until heated through.
0.25 cup water or white wine, 1.5 lbs Italian sausage links
Turn off heat and let the pan sit for 2-3 minutes so flavors meld. Taste and adjust seasonings with salt and pepper. Serve immediately with crusty bread, over pasta, or in hoagie rolls.