Heat a large skillet or wok over medium heat and add olive oil. Sauté the diced ham, onion, and red bell pepper until the onion is translucent and the vegetables are tender.
Push the ham and vegetables to the side of the skillet. Pour the beaten eggs into the cleared space and scramble until fully cooked, then combine with the ham and vegetable mixture.
Stir in the chilled brown rice and pineapple chunks to the skillet. Drizzle with sesame oil and soy sauce, mixing well. Cook until the rice is heated through and ingredients are well combined.