Add the sliced portobellos to a large skillet and add about ¼ cup of water. Over high heat, let the mushrooms cook in the water until all the water is evaporated. They will release their moisture and make more water as they cook. 

When all the water has evaporated, add a drizzle of vegetable oil to the pan and sauté the mushroom until they are browned on both sides. Transfer the mushrooms to a plate.

To the now empty pan, Over high heat, add another drizzle of vegetable oil and toss in the peppers and onions. Season with ½ teaspoon of kosher salt. Sauté until softened and charred in spots. 

Reduce the heat to medium, add the mushrooms back to the skillet. Add the garlic, cumin, smoked paprika, chipotle powder and remaining ½ teaspoon of kosher salt. Cook and stir for about 30 seconds, then stir in the Worcestershire sauce and the ketchup. Cook and stir until all the vegetables are coated in the sauce, about 1 more minute. 

Serve in warm tortillas with cilantro leaves, lime wedges, fresh jalapeños and sour cream (if desired).