• Trim the ends from the squash; cut the squash in half crosswise, then lengthwise into ½-inch-wide wedges.
• Remove the stem, ribs, and seeds from the bell pepper; thinly slice the bell pepper.
• Remove the stem, ribs, and seeds from the poblano; thinly slice the poblano crosswise. Wash your hands after handling.

In a large frying pan over medium heat, warm 1 to 2 teaspoons oil until hot but not smoking. Add the squash, season with salt and pepper, and cook, stirring occasionally, until just tender and lightly browned on all sides, 3 to 5 minutes. Transfer to a plate. Warm 1 to 2 teaspoons oil in the pan over medium heat. Add the bell pepper and poblano, season with salt and pepper, and cook, stirring occasionally, until they begin to soften and char, 3 to 5 minutes. Return the squash to the pan; remove from the heat.
While the vegetables cook, prepare the black beans.

• Rinse the black beans.

In a small sauce pot over medium heat, warm 1 to 2 teaspoons oil. Stir in the taco seasoning; cook until fragrant, about 30 seconds. Add the beans and ½ cup water; season with salt. Bring to a boil, reduce to a simmer, and cook, stirring occasionally, until most of the liquid has evaporated, 5 to 6 minutes.
While the beans cook, prepare the slaw and heat the tortillas.

• Cut away any core from the cabbage; thinly slice the cabbage.
• Juice half the lime; cut half into wedges for garnish.
• Coarsely chop the cilantro.

In a medium bowl, combine the cabbage, lime juice, and cilantro. Season lightly with sugar, if desired. Season to taste with salt and pepper; toss to combine.

On the stovetop directly over a flame, or in a dry medium frying pan over medium heat, warm the tortillas until just pliable and warmed through, about 30 seconds per side. Transfer to a clean kitchen towel, cover, and keep warm.

Transfer the tortillas to individual plates, fill with the beans, and top with the squash-pepper mixture. Garnish with the cabbage slaw, queso fresco, and pumpkin seeds. Serve with the lime wedges.