Add butter to a heavy bottom cast iron pot until melted and then add the onion, mushrooms, carrots, couple pinches of salt and some pepper and saut until soft.
Then add the garlic and a splash of the vinegar and continue cook until all is caramelized (this takes time and you dont want the mix to stick so watch your heat and take your time)
Once caramelized add the sausage and continue to fold the mix together while constantly breaking the sausage up and cooked through
Hand crush the tomatoes into the pot and add the residual sauce in the can. Add two healthy tbsp of tomatoes paste, the basil and season with pinches of salt and then sugar to balance the acidity.
Bring to a simmer, cover and lower the heat and cook for about 45 minutes. Check seasoning and then cook for an additional 30 uncovered and serve with whatever pasta you prefer with it, here I did cheese tortellini.
