Preheat your oven to 425°F and line a baking sheet with parchment paper or lightly coat with cooking spray.
In a shallow bowl, combine the almond flour, egg white, garlic powder, ginger powder, salt, and pepper. Mix until a smooth batter forms.
Pat the chicken breast dry and dip each piece into the almond flour mixture, ensuring an even coating.
Place the coated chicken on the prepared baking sheet. Lightly spray the top with cooking spray to help crisp the coating.
Bake in the preheated oven for about 18-22 minutes or until the chicken is cooked through and the coating turns golden and crispy.
While the chicken bakes, prepare the sweet and sour sauce by combining pineapple juice, tomato paste, rice vinegar, a pinch of salt, and pepper in a small saucepan. Warm over medium heat, stirring frequently until slightly thickened.
On a separate baking tray, spread out the sliced red bell peppers. Roast in the oven for the last 10 minutes of the chicken's baking time, or until the peppers are tender and slightly charred.
Remove both the chicken and peppers from the oven. Drizzle the sweet and sour sauce over the chicken, and serve with the roasted bell peppers on the side.
Enjoy your meal while it's warm.