For chili, heat oil, 1 turn of the pan, over medium-high heat in cast iron skillet or Dutch oven. Brown meat, season with salt and pepper. Add onions, garlic, spices, Worcestershire and cook a few minutes to soften onions, stirring frequently. Add tomato paste, stir 1 minute until fragrant. In a small bowl, whisk together stock and Masa or cornmeal. Add to chili along with beans and tomatoes with chilies. Bring to a bubble then reduce heat to a simmer to thicken.
For rice, bring broth to a boil. Add oil or butter, and rice, and season with salt and pepper. Cook 15 minutes. Finely chop spinach and cilantro with lime juice in a food processor. (Return processor bowl to base for the Avo-Sour Cream.) Add greens to rice, remove from heat, let stand 5 minutes.
For queso sauce, melt butter in medium saucepot over medium heat. Add shallots, garlic and chili pepper, and stir to soften 3 minutes. Season and stir in cornstarch then add milk. Bring to a bubble then stir in cream cheese. Once melted, add remaining cheese, a handful at a time, and stir to melt. Keep warm over low heat.
For Pico, toss together tomatoes, onions, jalapeño or Serrano, cilantro and salt to taste.
For Avo-Sour Cream, add avocado, sour cream and lime juice to the food processor and pulse to combine.
Char tortillas 30-45 seconds on each side over an open flame on a gas burner or in hot, dry skillet on an electric stove.
Working down the center of the tortillas, leaving 1 1/2 to 2 inches at either end to edge, build burritos with some pickled jalapeños, avocado cream, pico, Fritos, queso sauce, beef chili and rice. Tuck in tortilla top and bottom then rotate burrito a quarter turn and wrap and roll sides. Cut in half to serve.