Position a rack in the center of the oven and preheat to 400°F. Line a rimmed baking sheet with parchment paper.
In a large bowl, combine the ground chicken or turkey, panko breadcrumbs, egg, finely chopped green onions, chopped cilantro (if using), grated ginger, chopped garlic, 1 tablespoon soy sauce, 2 teaspoons sesame oil, and 1 teaspoon Sriracha.
Use a fork to break up the egg yolk and gently mix the ingredients until just combined, switching to your hands if needed; avoid overworking the mixture.
Scoop the mixture by tablespoonfuls and roll into 1 to 1½-inch meatballs (about 18–20 total). Place them on the prepared baking sheet with a little space between each.
Brush the tops and sides of the meatballs with the canola oil.
Bake until an instant-read thermometer inserted into the center registers 165°F, about 10 minutes.
While the meatballs bake, make the sauce: in a medium saucepan combine 2/3 cup water, 1/3 cup reduced-sodium soy sauce, 1/4 cup creamy peanut butter, 3 tablespoons honey, 1 tablespoon rice vinegar, 1 minced garlic clove, 1 teaspoon grated ginger, and 1 teaspoon Sriracha. Whisk to combine.
Heat the sauce mixture over medium-high, bringing it to a boil. Whisk constantly while it bubbles for about 30 seconds to 1 minute, until smooth and slightly reduced. Stir in 1 teaspoon sesame oil and remove from heat; sauce will thicken as it cools.
Serve the meatballs over rice with vegetables, drizzle generously with the peanut-sriracha sauce, and sprinkle with sesame seeds, additional green onions, and cilantro if desired.
