Place kale and mixed greens in a large bowl with cold water and some salt. Salt will draw out any dirt and bugs. Drain and give it a final rinse, and place in a salad spinner. Then place the kale and mixed greens in a large serving bowl.
To make the maple glazed pecans, add tablespoon of butter to a skillet, over low-medium heat, once butter is melted, add the pecans, 2 tablespoons of maple syrup and pinch of salt. Coat the pecans with the maple syrup and continue to stir for about 10 minutes until the pecans have harden and crystalized. Set aside to cool.
Arrange red onion, sliced avocado, blueberries, goat cheese and pecans.
In a blender or food processor, add the blueberries, balsamic vinegar, honey, lemon, Dijon and begin blending, slowly add the olive oil, salt and pepper. If it's too thick in texture, add a couple of tablespoons of water and blend well.
Drizzle the dressing over the salad and serve.
Notes
Note: This blueberry vinaigrette will store in the refrigerator for up to 6-7 days.