To make the queso, heat the over to 350 degrees F and line a rimmed baking sheet with parchment. Halve the squash and removed the seeds. Rub the squash all over with olive oil and sprinkle with sea salt. Place squash cut side down on the baking sheet and bake until very tender, about 60 minutes. Set aside until cool enough to handle then scoop the squash out, leaving the skin behind. You'll need 2 cups of the squash puree.

In the bowl of a food processor, pulse to combine 2 cups squash, strained pumpkin seeds, nutritional yeast, pickled jalapeños, garlic granules, and sea salt. With food processor running, drizzle in jalapeño pickle juice a little at a time, adding enough to give you a pillowy, spreadable texture. Add more salt, jalapenos, or garlic powder to taste. Scrape queso out of the food processor.

Meanwhile, prep the rest of the ingredients.

 Cut the onion half into two sections. Mince enough of one section to give you 1/4 cup. Slice the rest of the onion into paper thin slices. Then cut those into 1-inch segments.

Set a medium saucepan over medium heat. When hot, add the oil and 1/4 cup minced onions. Cook 5 - 7 minutes, then add the cumin, chili powder and cook 1 minute more. Add beans and their liquid. Bring to a gentle simmer, then turn heat to low and cook, stirring occasionally and smashing some of the beans against the side of the pan, for 20 minutes.

To assemble the nachos, with oven still at 400 degrees F, set out a 9 x 13-inch baking dish. Cover the bottom with half the tortilla chips. Add swoops of queso and half the beans, and scatter some of the sliced red onions. Add remaining chips, another layer of queso, the remaining beans, and some of the red onions. Set nachos on the middle rack in the oven, and bake for 4 - 6 minutes, or just until everything is hot and the chips are starting to edge golden.