Preheat your oven to broil. Line two baking sheets with parchment paper, ensuring that the one used for the cauliflower rice and tofu mixture is quite large.
Start the poblano cream. Place the poblano pepper directly on the oven rack below the broiler. Let the pepper char for a minute or so and then carefully flip it over with tongs. Broil for another minute or so. Repeat this process until it is evenly charred.
Remove the poblano from the oven and place it in a bowl. Cover the bowl with plastic wrap and set aside for 5 minutes.
Lower the heat to 425°F.
Drain the cashews. Then, in an upright blender, combine the cashews, garlic, nutritional yeast, lime juice, salt, pepper, and water. Remove the plastic wrap from the bowl with the poblano pepper and peel the charred outer skin off. Once that’s off, remove the stem and seeds and transfer to the upright blender. Blend this mixture on high until smooth and creamy. Check the cream for seasoning, adjust if necessary, and set aside.
Make the cauliflower rice and tofu filling. Get two separate medium bowls out. Place the cauliflower rice in one bowl and the torn up bits of tofu in the other. In the bowl with the cauliflower, add 2 tablespoons of the olive oil, 1 teaspoon nutritional yeast, 1 teaspoon chili powder, 1 teaspoon of the ground cumin, 1 teaspoon of the garlic powder, 1 teaspoon of the onion powder, ½ teaspoon of the ground coriander, plus salt and pepper, to taste. Toss to combine.
In the bowl with the tofu bits, add the remaining olive oil, nutritional yeast, chili powder, ground cumin, garlic powder, onion powder, ground coriander, the adobo sauce, arrowroot starch, cornmeal, plus some salt and pepper. Toss to combine.
On one side of the large, parchment-lined baking sheet, spread out the coated cauliflower rice in a single layer. On the other side of the baking sheet, spread out the tofu in a single layer as well, trying to give as much space around the pieces of tofu as possible.
Remove the stems from the portobello mushrooms and place them on the other baking sheet. Spray all sides of the portobello mushrooms with oil spray and season with salt and pepper. Make sure that the gills side is facing up when you’re done.
Place both the mushrooms and the cauliflower rice mixture in the oven. Set a timer for 20 minutes.
At the 20 minute mark, remove the mushrooms from the oven. They should be soft and juicy. The cauliflower rice and tofu mixture will need another 10 minutes. Stir the cauliflower and tofu bits up before returning to the oven. You want everything to be golden brown and parts of the tofu should be crispy and golden when done.
Once you have the cauliflower rice and tofu mixture ready to go, give it a mix to combine everything together. Spoon this mixture into the cooked portobello mushrooms right on the baking sheet. Once they’re loaded up, transfer the stuffed portobello mushrooms back into the oven to heat through for about 10 minutes.
Once warmed through, serve the stuffed portobello mushrooms with the poblano cream and chopped cilantro on top.