Cut chicken into bite pieces. In a large bowl combine flour, baking powder, water and salt. Mix until thick and smooth. Place the chicken and coat nicely.
Fry chicken until golden brown and crispy for few minutes and transfer to a plate with paper towels.
In a small bowl combine water and cornstarch. Set aside.
In a saucepan, combine rice vinegar, pineapple juice, sugar, ketchup, and soy sauce. Bring to a slow boil then add the cornstarch mixture. Stir until thickened.
Heat 2 tablespoons of oil in a pan and saute the onions and peppers about few minutes. Season with salt and pepper then return the chicken and pour the sauce all over. Stir to combine. Serve
Recipe by Gluten-Free by Jan at https://glutenfreebyjan.com/gluten-free-sweet-and-sour-chicken-2/