Preheat oven to 425 F . Line large, rimmed baking sheet with parchment paper or a silicone mat.
Into food processor container, place all meatball ingredients and blend into a slightly chunky mixture, scraping down sides of container as needed. Roll mixture into golf ball-sized rounds and place on baking sheet. Bake for 15 minutes, flip balls, and bake for another 15 minutes.
To make buffalo sauce, in bowl, place cashews, cover with water, and let soak for at least 2 hours. Drain cashews and place in blender with 1 cup water and remaining sauce ingredients. Blend until smooth.
In medium pot on stovetop, place buffalo sauce and bring to a slight simmer. If sauce is too thick, thin with some additional water. Add balls and heat for 2 minutes, turning balls to coat. Serve on platter with carrot sticks and celery sticks and any extra buffalo sauce.
Per serving: 222 calories; 12 g protein; 4 g total fat (1 g sat. fat); 36 g total carbohydrates (7 g sugars, 11 g fiber); 641 mg sodium