Cut chicken thighs into 1-inch chunks and pat them dry with paper towels—this helps them brown better. In a small bowl, combine garlic powder, onion powder, salt, and pepper. Toss the chicken pieces with this seasoning mixture until evenly coated. Drain the pineapple slices in a strainer, reserving the juice in a measuring cup. Thinly slice the jalapeno into 1/8-inch rounds and chop the green onions, keeping them separate.

Heat the oil in a large skillet over medium-high heat until it shimmers. Working in batches if needed to avoid crowding, add the seasoned chicken and cook for 5-7 minutes per side until deep golden brown. I prefer avocado oil here because it has a high smoke point and won't break down at this temperature, which keeps the flavor clean. Transfer the browned chicken to a clean plate.

Pour 1/2 cup of the reserved pineapple juice into the same skillet over medium-low heat. Use a wooden spoon to scrape up any browned bits stuck to the bottom of the pan—these caramelized bits add deep flavor to your sauce. Once the pan is deglazed, stir in the BBQ sauce until smooth and well combined, allowing it to warm through for about 1-2 minutes.

Return the browned chicken to the skillet and add the drained pineapple slices. Gently stir everything together, making sure all the chicken pieces and pineapple are coated with the sauce. Let it simmer on medium-low for 2-3 minutes to let the flavors meld and warm through.

Transfer the skillet to your oven and broil on high for 5 minutes, watching it carefully to prevent the sauce from burning. The high heat will caramelize the edges and give the dish a slightly charred, restaurant-quality finish. Remove from the oven and immediately top with the sliced jalapeno and chopped green onions. The fresh, bright flavors of these toppings cut through the richness of the BBQ sauce beautifully.