Drain the pineapple juice into a small bowl. Set the drained can of pineapple to the side. Add the chicken stock, brown sugar, soy sauce and minced garlic to the bowl with the pineapple juice.
Place the chicken breasts in the base of the multi-cooker and pour the pineapple chunks around the chicken. Season with salt and pepper. Pour the pineapple-soy sauce mixture over the top.
SLOW COOKER: Cook on low for 8 hours. With 30 minutes left in the cooking cycle, swirl the cornstarch with a Tbsp of water and stir it into the sauce. Cook for 30 more minutes to allow sauce to thicken.
Cook the rice as directed.
Prepare veggies or salad.
Serve Slow Cooker Pineapple Chicken with sesame seed and green onion slice garnish, over rice with veggies or salad.