In a large bowl, combine the cubed watermelon and blueberries. Pour the lemon juice and stevia over the top.
Sprinkle on the mint and the vegan cheese, if using. Toss thoroughly to combine.
Toss the spinach and kale together in a large bowl. Top with the fruit and cheese mixture. Sprinkle with sea salt.
Notes
*Follow Your Heart and Violife have delicious varieties of vegan feta-style cheese crumbles. Great brands of dairy-free cheese include Daiya, Kite Hill, Follow Your Heart, Forager, Miyokos, So Delicious, and Violife.