Bring 6 quarts of water to a boil and add 2 tablespoons salt.
In a 12 to 14-inch saute pan, heat olive oil until just smoking. Add jalapenos and saute until tender, about 3 minutes. Add tomato sauce and cook over high heat until sauce comes to a boil. Add crabs, bring to a boil, then lower heat and simmer until crabs are cooked through, about 6 minutes.
Cook pasta in boiling water according to package directions, until tender yet al dente. Remove pasta from cooking water, drain and add to saute pan with tomato sauce and crabs. Add scallions and toss over high heat 1 minute. Divide pasta evenly among 4 warmed bowls and serve immediately, drizzled with extra-virgin olive oil.
In a 3-quart saucepan, heat the olive oil over medium heat. Add the onion and garlic and cook until soft and light golden brown, about 8 to 10 minutes. Add the thyme and carrot and cook 5 minutes more, until the carrot is quite soft. Add the tomatoes and juice and bring to a boil, stirring often. Lower the heat and simmer for 30 minutes until as thick as hot cereal. Season with salt and serve. This sauce holds one week in the refrigerator or up to six months in the freezer.