Preheat oven to 350 degrees and scrub the potatoes clean.
Prick the potatoes with a fork 6-8 times and bake on a pan for 1 hour and 15 minutes, or until cooked through. To make the potato skin extra brown and crispy, brush with olive oil before baking.
Once cooked, let the potatoes cool for 10-15 minutes.
Meanwhile, make the cheese sauce: Cook the squash either by roasting it alongside the potatoes for about 20 minutes, or steam it. I used my Instant Pot and cooked on high pressure for 4 minutes with 1 cup of water added.
Add the cooked squash, the soaked and drained cashews and the rest of the sauce ingredients to blender. Blend on high until very smooth. Set aside.
Steam the broccoli for 8 minutes. Set aside.
Next, slice the potatoes in half lengthwise and scoop out the flesh into a large bowl leaving about 1/4 inch of flesh so the potatoes retain their shape. Add about 3/4 of the sauce and mash with a potato masher or use a hand mixer.
Add more cheese sauce if desired (this will depend on how large your potatoes are, there should be some leftover sauce though). Now stir in the steamed broccoli. Spoon the mixture back into the potato skins, filling quite high. Sprinkle with non-dairy cheddar shreds if desired.
Bake at 350 degrees for 20 minutes. Serve with more cheese sauce drizzled on top if desired.