½ - 1 stick unsalted butter
½ red onion, finely chopped
3 garlic cloves, minced
1 (28oz) can crushed San Marzano tomatoes
½ cup vodka
1 cup heavy cream
1 tsp sugar
¼ cup fresh basil
In a Dutch oven or large saucepan, melt the butter over medium heat. Add the onions and sauté for 5–7 minutes, until soft and translucent. Stir in the garlic and cook for another 30 seconds, until fragrant.
Carefully add the vodka and let it simmer for about 8 minutes, allowing the alcohol to cook off and reduce slightly.
Stir in the tomatoes, sugar, and basil. Bring to a simmer and cook uncovered for 30 minutes, stirring occasionally, until the sauce thickens.
Reduce the heat to low and stir in heavy cream. Simmer for another 15 minutes, stirring occasionally, until the sauce is smooth and creamy.