Preheat oven to 400 degrees F (convect/fan). Cut acorn squash in half, scoop out seeds, and place halves on a large baking tray, flesh-side up. Brush flesh with ½ tbsp. avocado oil and ¼ tsp. each of the kosher salt and pepper. Place tray into oven and bake for 20 min, then remove from oven.
Meanwhile, slice potatoes into quarters. Place them onto remaining tray space with squash (after it has cooked for 20 min). Drizzle potatoes with remaining 1 to 1 ½ tbsp. avocado oil and ¼ tsp. each kosher salt and pepper, toss. Place tray back into oven for another 35 to 40 min, flipping potatoes halfway, until potatoes are crisp and tender, and squash flesh is soft. Potatoes or squash may not be ready at exactly the same time, depending on sizes.
Cook quinoa according to package directions, then transfer to a serving tray or mixing bowl to cool. Stir in 2 tsp. olive oil and juice of ½ lemon. Season with pinch of salt and pepper if desired.
Thinly slice the red onion and halve the cherry tomatoes. When squash has cooled a bit, cut into crosswise slices (you can remove skin when eating). Top quinoa with squash, roasted potatoes, red onion, tomatoes, 4 servings pita chips, ¼ cup crumbled vegan feta, 1/3 cup to ½ cup Bitchin’ Sauce, and 2 tbsp. fresh parsley.