"Nowadays many people are following the autoimmune paleo protocol (AIP). This restricted version of the paleo diet, in addition to prohibiting grains, legumes, and dairy, also excludes eggs, nuts, seeds (including seed-based spices) and nightshades (potatoes, peppers, eggplant, and tomatoes) in an effort to minimize and in some cases to cure leaky gut and many autoimmune diseases.
But you know how it is, we Italians love our tomato sauce."
Combine kabocha squash, carrots, and beet in a food processor; pulse until coarsely grated.
Heat olive oil in a saucepan over medium heat until sizzling. Add onion, garlic, and sage; cook and stir until onion is fragrant, about 1 minute. Stir in grated kabocha squash mixture, capers, Italian herbs, and salt.
Pour water into the saucepan. Cover and simmer sauce, adding more water if needed, until kabocha squash mixture is soft, about 30 minutes. Mash mixture with a fork to make sauce smoother.
Stir lemon juice and basil into the sauce and let flavors combine, about 1 minute.