For the Ranchero Sauce: Place a skillet over medium heat and add the oil and shallots. Saute the shallots for 2 minutes. Then add the garlic and saute another 1-2 minutes. Add all remaining ingredients, except for the heavy cream. Simmer the ranchero sauce for 10 minutes. Remove from heat. Using an immersion blender
, puree the ranchero sauce until smooth. Then stir in the heavy cream. Salt to taste.