Preheat the oven to 425°F and line 2 baking sheets with parchment paper.
On one baking sheet roast the whole poblanos, halved shallots, and garlic for 20 minutes or until the shallots are nicely browned and the poblanos are charred.
Make the Crispy Squash: In a small bowl, combine the ground flaxseed with the almond milk and set aside to thicken for 5 minutes. Note: If the mixture becomes too thick as you work, thin with a tiny bit more almond milk. In a medium bowl, combine the panko, hemp seeds, chili powder, onion powder, and the salt. Dip each butternut squash cube in the flaxseed mixture and then the panko mixture. Place the cubes onto the second baking sheet and drizzle with olive oil. Bake for 35 to 40 minutes or until browned and crispy.
Make the Poblano Sauce: In a food processor, combine ½ of one roasted poblano, ½ of one roasted shallot (you will use the remaining poblano and onion in the taco filling), the peeled roasted garlic, the mayonnaise, cilantro, lime juice, salt, and pepper. Blend until smooth, leaving some remaining green flecks. Chill until ready to use.
Slice the remaining poblanos and shallot and set aside. Place the shredded cabbage into a medium bowl, add a heaping scoop of the poblano sauce, and toss until combined.
Fill each tortilla with the cabbage, sliced poblanos and shallots, the butternut squash, avocado, cilantro, a scoop of aioli sauce, and the serrano peppers, if using. Serve with the remaining sauce and the lime slices.
Recipe by Love and Lemons at https://www.loveandlemons.com/crispy-butternut-squash-poblano-tacos/