Whisk together the lime juice, fish sauce, sweetener of your choice and red chili flakes to make the dressing.
Thinly slice and chop enough red and green cabbage to make 3-4 cups of sliced cabbage. Put the cabbage in medium-sized bowl and toss with the dressing. Let the cabbage marinate while you prepare the other ingredients.
Slice the green onions. Wash and spin dry the mint leaves and cilantro, using a salad spinner or drying with paper towels, then chop enough to make 1/2 cup each chopped mint and cilantro. Coarsely chop peanuts.
Add the green onion, chopped mint, chopped cilantro and most of the peanuts to the cabbage and toss to combine. Garnish with additional chopped peanuts. Best if served immediately.