Preheat oven to 375 degrees. Add the olive oil to a medium saucepan. Once the oil is heated, add the onions and garlic. Saute until the onion is translucent and the garlic is fragrant. Add a nice pinch of kosher salt and a few cracks of black pepper.
Add the jalapeno and saute until the pepper is softened. Add in the tomato paste and let it cook for a few minutes. This will allow the acid flavor to cook out and also for some brown bits to form flavor on the bottom of the pot.
Add the crushed tomatoes and add another nice pitch of salt and cracks of pepper. This is building layers of flavor
Add in the stock and add in the spices. Stir until everything is well combined. Let this sauce cook for at least an hour, no more than an hour and a half. Check the seasoning and add salt and pepper as needed.
While the sauce cooks, heat the flour tortillas for about 30-45 seconds in the microwave to soften them and make them pliable to roll.
Grate the cheese, I like to grate my own as the pre-grated doesn't melt as nicely. Mix the cheeses together and reserve about 1/4 cup for the top. Use the rest to roll up in the tortillas.
To assemble, lay down a thin layer of the chili sauce, top with the rolled, cheese filled tortillas. Top with a generous amount of the chili sauce and the reserved shredded cheeses.
Bake covered, (tip-cover with plastic and then foil and the foil won't stick to the cheese as it melts and it will help melt it evenly), for 30 minutes. Uncover it and bake it for another 15-20 minutes until it is golden brown and bubbly.
Serve with freshly made guacamole and/or sour cream and fresh cilantro. ENJOY!