Preheat oven to 400 degrees F. Line a baking sheet with parchment paper. Set aside.
Combine ground chicken, basil, lime zest and juice, breadcrumbs, egg, mustard, mayonnaise, paprika, salt, and pepper in a large bowl. Stir with a large spoon until well combined.
Using your hands, shape the ground chicken mixture into 12 meatballs and arrange on the prepared baking sheet so that they do not touch. Place into the oven and bake for 22-25 minutes, or until meatballs are fully cooked through.
In a medium bowl, toss together tomato cucumber avocado salad ingredients until well combined, set aside.
Heat a medium size saucepan over medium/low heat. Add polenta and 1/4 cup milk to the saucepan. Gently break apart with a large wooden spoon or fork as it heats up. Add additional milk in 1/4 cup increments. Cook for 7-9 minutes until creamy. Remove from heat. Stir in Parmesan.
Serve meatballs with creamy polenta, fresh sliced basil, and tomato cucumber avocado salad.