Preheat the oven: Set to 400°F (200°C). Line a rimmed baking sheet with parchment paper or foil and lightly oil it to prevent sticking.
Make the meatball mixture: In a large bowl, combine ground chicken, egg, almond flour, mayonnaise, parsley, garlic, onion powder, salt, pepper, and smoked paprika or cayenne if using.
Mix gently with a fork or your hands until just combined. Do not overmix or the meatballs can turn dense.
Shape the meatballs: Lightly oil your hands. Scoop about 2 tablespoons of mixture per meatball and roll into balls, placing them on the prepared sheet. You should get about 20–24 meatballs.
Bake: Cook for 12–15 minutes, or until the centers reach 165°F (74°C).
If you want some browning, broil for 1–2 minutes at the end. Let them rest for 3 minutes.
Make the Buffalo sauce: While the meatballs bake, melt butter in a small saucepan over low heat. Stir in hot sauce, vinegar, and garlic powder until smooth.
Keep warm on the lowest heat.
Toss to coat: Transfer baked meatballs to a large bowl. Pour over the warm Buffalo sauce and gently toss until every meatball is glazed.
Serve: Plate with celery and cucumbers. Top with chopped green onions and a sprinkle of blue cheese if you like.
Offer ranch or blue cheese dressing on the side.