In large bowl, whisk together chickpea flour, water, garlic powder, sambal oelek (if using), salt and pepper. Stir in nutritional yeast and green onions; let stand 15 minutes.
Preheat oven to 200°F. Line baking sheet with parchment paper or silicone mat.
Heat 9-in non-stick frying pan or cast-iron skillet over medium-high heat. Brush pan with ½ tsp of the oil using silicone brush.
Stir batter, then pour about ⅓ cup into centre of pan, swirling to spread evenly. Cook until edges and bottom are browned, about 3 minutes. Flip and cook until lightly brown, 1 to 2 minutes. Transfer to prepared baking sheet and put in oven to keep warm.
Reduce heat to medium and repeat with remaining oil and batter.
Serve pancakes with salsa, sliced avocado, chili flakes and more green onions, if desired.