Preheat oven to 400 degrees F (204 C) and prep your jalapeños, splitting in half, removing the tops, and then spritzing or brushing them with a bit of olive oil. Place in rows facing up (see photo).
If you’re using crushed tortilla chips as a topper (recommended), toast them while prepping your cheese sauce by spritzing them with olive oil and baking them for 8-10 minutes or until golden brown, watching closely as they can burn fast.
To a small saucepan over medium heat, add the onion and garlic with a bit of olive oil and cook until just softened and fragrant – about 5 minutes. Set aside.
Add soaked cashews, garlic, onion, nutritional yeast, cumin, vegetable broth and green chilies to a blender and blend until creamy and smooth, using the “liquify” or “puree” option if you have it. If the sauce is too thick, thin with more vegetable broth. If too thin, add a handful of raw cashews and blend again.
Spoon or pipe the cheese mixture into the jalapeños, generously filling. You’ll have leftovers, which you can reserve for nachos or just dip. Top with crushed, toasted tortilla chip crumbs and bake for 15 minutes or until the jalapeños are soft and the cheese has deepened in color.
Place the pan on the top rack and broil for the last minute or two for an even more intense color/flavor.
Serve immediately, sprinkling with a bit of red pepper flake for garnish (optional). Store leftovers covered in the fridge for up to a few days, reheating in the microwave or a 350-degree F (176 C) oven until warmed through (though best when fresh).
*Nutrition is a rough estimate for 1 of 20 poppers with a tortilla crumb topping (I also took into account about 3/4 of the cheese since you have quite a bit leftover for other uses).