Preheat oven to 425 F
Toss bell pepper with vegetable oil and a pinch of salt and transfer to a foil lined baking sheet. Roast peppers until skin begins to wrinkle and there are some charred spots, 20-25 minutes. Transfer to a bowl and cover with cling film for 5 minutes, allowing the skin to loosen and making them easier to peel. Remove cling film, peel peppers and remove seeds, then slice peppers into ¼” strips.
In a large skillet or heavy bottom pot set over medium-high heat, warm 1 tbsp olive oil, and brown sausages, about 3 minutes on each side. Slice into ¾” pieces and set aside on a plate. It’s okay if sausages are undercooked at this point as they will finish cooking in the sauce.
In the same pan, heat remaining 2 tbsp olive oil and sauté onions until softened, about 4-5 minutes. Stir in garlic, sauté another 30 seconds then stir in tomato paste and deglaze with red wine. Bring to a simmer to cook off alcohol, then add crushed tomato and oregano along with roasted peppers, sausages and any accumulated juices. Cover and reduce heat to low and let simmer about 20 minutes, stirring often. Make sure sausages reach an internal temperature of 165 F when probed with a thermometer.
In a pot of heavily salted boiling water, cook tagliatelle as per package instructions until al dente. Drain pasta and toss with a few tablespoons of sauce and torn basil leaves then transfer to a serving dish. Top with remaining sauce, freshly grated Parmigiano-Reggiano and a good drizzle of extra virgin olive oil.