Step 1

Whisk soy sauce, salt, pepper, garlic powder, and cumin together in a large glass or ceramic bowl. Add chicken medallions and toss to evenly coat. Set aside to marinate.

Step 2

Combine pineapple chunks, syrup, and sugar in a medium pot over medium-high heat; bring to a boil. Boil until sugar has dissolved, 2 to 3 minutes. Remove from the stove, transfer pineapple chunks to a bowl, and leave syrup in the pot.

Step 3

Place potato starch in a bowl. Dredge marinated chicken medallions in potato starch; shake off excess.

Step 4

Heat 1 tablespoon vegetable oil in a large skillet over medium-high heat. Add chicken, working in batches and adding more oil if necessary, and fry until golden brown and crunchy, about 3 minutes per side. Transfer to a paper towel-lined plate.

Step 5

Heat remaining 1 teaspoon vegetable oil in a wok. Add tomato paste; cook and stir until paste darkens, being careful it does not burn. Add bell pepper and cook until slightly softened but still crispy, 1 to 2 minutes. Mix in chicken medallions and pineapple chunks. Slowly mix in some of the syrup until mixture is lightly glazed; reserve remaining syrup for another use. Sprinkle with green onions.