Preheat outdoor grill or a cast iron skillet over medium heat.
In a large bowl or plastic bag, add balsamic vinegar, juice of 1/2 lime, chili powder, cumin, garlic powder, paprika, salt and pepper; stir to combine.
Add portobello mushrooms; toss to coat mushrooms. Let them sit for at least 15 minutes, flipping and stirring the mushroom caps.
Remove corn husks. Using a grill pan, grill corn and bell peppers until browned, about 10-15 minutes. Rotate corn to brown on all sides. (If you don’t have a grill, sauté peppers until tender and browned, about 10 minutes. Place corn on a baking sheet, broil for 5 minutes, flip, then broil for 5 more minutes.)
Place mushrooms on the grill, or a skillet. Cook for 10-15 minutes, until browned.
Add black beans, cabbage, and kimchi to individual bowls to prepare for serving.
When the vegetables are fully cooked, remove from grill or skillet. Slice mushrooms thinly. Cut corn off the cob. Place all vegetables on a serving plate.
Assemble your mushroom tacos by placing a tortilla on a plate and adding mushrooms, bell peppers, corn, black beans, cabbage, and kimchi. Top with jalapeño slices, a squeeze of remaining lime juice, and a sprinkle of cilantro.