Preheat oven to 425 F.
Add potatoes to a large pot, cover with water, and bring to a boil. Cook for about 30 min until potatoes are tender and easily pierced with a fork. Drain in a colander and let potatoes set for 5 minutes to cool.
Add the potatoes to a bowl along with 1 ½ tbsp olive oil, a dash of garlic powder and onion powder, and salt and pepper. Toss until potatoes are coated, and add to a parchment paper lined baking sheet. Smash the potatoes with the bottom of a glass, and then drizzle on a little more olive oil. Bake for about 40 minutes until potatoes are golden and crispy.
Make your yogurt ranch by whisking together ingredients in a small bowl. Thin out the dressing to your desired consistency, starting with 1 tbsp water.
When potatoes are ready, let cool slightly, and then break up into smaller pieces with your hands. Add to a large bowl along with chickpeas, celery, cucumbers, red onion, avocado, and parsley. Toss in the ranch dressing along with another small pinch of salt and crushed red pepper. Serve immediately.
