Cut the chicken thighs into 1-inch bite-sized pieces.
In a medium bowl, combine the chicken pieces with the egg white, 1/2 tsp kosher salt, and cornstarch. Toss until every piece is evenly coated.
Let the chicken marinate for 15 minutes at room temperature, or cover and refrigerate for up to overnight.
Cut the red and yellow bell peppers into 1-inch chunks and set aside.
Mince the fresh ginger and set aside.
In a small bowl, whisk together the pineapple juice, white vinegar, ketchup, remaining 1/2 tsp kosher salt, and brown sugar until the sugar dissolves. Set the sauce aside.
Drain the pineapple chunks and set aside, reserving the juice if using canned.
Steps
Heat a large wok or 12-inch frying pan over high heat for about 2 minutes, until a drop of water flicked into the pan instantly sizzles and evaporates — the pan must be very hot for a proper stir-fry.
Add 3 tsp of the cooking oil and swirl to coat the bottom and sides of the pan.
Add the marinated chicken pieces in a single layer. Do not stir or move them — let them fry undisturbed for 1 minute until the bottoms are browned and lightly caramelized.
Flip each piece and fry for another 1 minute on the second side. The chicken will still look slightly pink in the center at this stage — that is fine, as it will finish cooking later.
Transfer the partially cooked chicken to a clean plate, leaving as much oil in the pan as possible.
Reduce the heat to medium and add the remaining 1 tsp of cooking oil. Let it heat for about 30 seconds.
Add the bell pepper chunks and ginger. Stir-fry for 1 minute, tossing frequently, until the peppers are slightly softened but still crisp and vibrant.
Add the pineapple chunks and pour in the sweet and sour sauce. Stir everything together and increase the heat back to high.
Bring the sauce to a simmer, stirring occasionally, about 1 to 2 minutes. It will begin to thicken slightly as it heats.
Once the sauce is simmering, add the chicken pieces back into the pan. Toss to coat everything evenly.
Let the chicken simmer in the sauce for 1 to 2 minutes, until fully cooked through — the internal temperature should reach 165°F (74°C). To check without a thermometer, cut into the thickest piece; the flesh should be completely opaque with no pink remaining. If still pink, cook for 1 more minute.
Taste the sauce and adjust seasoning — add a little more brown sugar for extra sweetness or a splash more vinegar for extra tang.
Serve immediately over steamed white or brown rice while hot.
Cook this hands-free with Sue
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