Heat the oven to 375°F. Line a rimmed baking sheet with parchment paper.
Warm the olive oil in a large skillet over medium heat. Add the mushrooms and onion. Cook for 8 to 10 minutes, stirring often, until the vegetables soften and most of their moisture has evaporated. Set aside to cool for about 10 minutes.
In a large mixing bowl, combine the ground turkey, cooled mushroom mixture, egg, breadcrumbs, tomato paste, chipotle peppers, cumin, smoked paprika, salt, and black pepper. Mix gently until just combined.
Shape the mixture into a compact loaf on the prepared baking sheet. Bake for 40 to 50 minutes, until the center reaches 165°F. Rest the meatloaf for 10 minutes, then crumble it into bite-size pieces with a fork.
While the meatloaf bakes, combine the cabbage, cilantro, and lime juice in a bowl. Toss well and set aside so the cabbage softens slightly.
Warm the corn tortillas in a dry skillet over medium heat, turning once, until pliable. Divide the crumbled meatloaf among the tortillas and top with the cabbage slaw.