Place the cauliflower into a food processor and process until broken down and rice-like. Set aside.
Heat the coconut oil in a large, high-sided frying pan on medium-high heat. Add in the chicken and green onion and cook, breaking up the chicken, for 2 minutes.
Add in the cauliflower rice and cook until the chicken is lightly browned, about 2-3 minutes.
Add in the Napa cabbage, stirring to combine. Cover the pot, turn to medium heat, and cook, stirring occasionally, for 3 minutes.
Uncover the pot and add in the pineapple juice, fish sauce, lime juice, and sriracha, stirring to combine. Turn the heat to high and bring to a boil. Once boiling, boil for 3 minutes or until most of the liquid evaporates, stirring frequently so the bottom doesn't burn.
Remove the pan from the heat and stir in the cucumber, cilantro, and mint. Season to taste with salt, if needed.