Heat olive oil over medium heat in a medium stock pot.
Add onions and cook 4-5 minutes, stirring occasionally until soft. Add garlic and stir to combine. Let garlic cook until fragrant, 2-3 minutes, stirring frequently so the garlic doesn’t burn.
Add crushed tomatoes, stock, basil, coconut milk, salt, garlic salt, pepper. Stir to combine.
Either move the pot off of the stove or turn the heat off and blend with an immersion blender until smooth. (Or blend in a standard blender and return to the pot. *See notes below). Once fully puréed return the pot of soup to the stove over low heat.
Add vinegar and sugar and stir to combine.
Simmer 20 min on very low heat to allow flavors to combine, stirring frequently.
Serve in shot glasses topped with chopped fresh basil, chopped green onions or just some fresh cracked black pepper.