In a medium saucepan, melt butter over medium heat until melted.

Add chopped onion, oregano, and salt. Cook for 3-5 minutes until onion has softened and becomes translucent, stirring occasionally.

Add garlic and combine with ingredients.

Stir in crushed tomatoes and sugar. Increase heat to medium-high heat and bring to a simmer and then reduce heat to medium-low.

Cook for 10 minutes and allow sauce to thicken a bit.

Remove from heat and stir in olive oil and basil.

Season with salt if necessary and black pepper.