In a large mixing bowl, whisk together the flour, cornstarch, and water until smooth to create a thick batter.
Add the bite-sized chicken pieces into the batter, ensuring each piece is well coated. This creates a crispy outer layer when fried.
Heat vegetable oil in a deep fryer or large pot over medium-high heat until it reaches 350°F (175°C). Use a thermometer for accuracy.
Carefully drop the battered chicken pieces into the hot oil, working in batches to avoid overcrowding. Fry for 4–5 minutes until golden brown and crispy, then remove with tongs and drain on paper towels.
In a saucepan, combine pineapple chunks, vinegar, brown sugar, and soy sauce. Bring to a gentle boil over medium heat, stirring occasionally.
Simmer the sauce for 5–7 minutes until it thickens slightly and the pineapple releases its aroma, filling your kitchen with a sweet and tangy scent.
Pour the hot sauce over the fried chicken bites in a large bowl. Toss gently to coat each piece evenly with the sticky, flavorful glaze.
Transfer the coated chicken bites to a serving dish, arranging them attractively for a snack-sized, crispy, and glossy presentation.
Serve immediately while crispy and hot, allowing the glaze to stick and enhance each bite with a perfect balance of sweetness and tang.
