Preheat oven to 400 degrees Fahrenheit.
Add ground chicken, salt and pepper, 2 tbsp of pineapple juice, 2 tbsp of coconut aminos, garlic, egg, almond flour, and 2 tbsp of pineapples (diced) into a large bowl. Use your hands to combine all of the ingredients.
Once all of the ingredients are combined, use a tablespoon measure to grab the mixture and roll it into meatballs. The mixture is very soft so just do your best. You can add it to the refrigerator to try and frim them up a little more for an hour if you have time but it is not necessary. Add meatballs to a baking dish and bake in the oven for 25 minutes.
Time to make the sticky sauce. Add 1 cup of pineapple juice, 1/2 cup of coconut aminos, 1/2 tsp of ground ginger to a medium-sized pot over medium heat. Whisk ingredients together.
In a separate cup, make a slurry and combine 1/2 cup of water with arrowroot starch. When the sticky sauce is hot, add the slurry (water and arrowroot starch) to the sauce. Whisk sauce until it is thick. Lastly, fold in 1 cup of pineapple chunks.
When the meatballs have finished cooking, remove from oven and pour sticky sauce over the top. Garnish with green onions and toasted sesame seeds (optional).