In a large heavy-bottomed pot, heat the olive oil over low heat. Add the onions and cook until soft, about 3-5 minutes.
Add the riced cauliflower to the pot. Increase the heat to medium and continue to cook, stirring occasionally until the cauliflower begins to take on a light golden color.
Pour in the Barilla® Traditional sauce, lentils, and crushed red pepper. Mix until well combined. Place the lid on top and bring the sauce to a gentle boil. Reduce the heat to low and simmer with the lid on for about 10 minutes or until the riced cauliflower is soft. The sauce should be thick. Season with salt and pepper, to taste.
Bring a large pot of salted water to a boil. Cook the Barilla® fettuccine according to the package instructions.
Serve pasta with cauliflower bolognese sauce. Garnish with fresh basil and Parmesan cheese, if desired.
