Place a rack in the centre of the oven and preheat to 400 degrees.
Trim the greens, tops and stems from the beets. Wash thoroughly and wrap in aluminum foil packages.
Peel and remove seeds from pumpkin and cut 2 cups into a chunky dice. Toss in 1 tablespoon of olive oil.
Place the beet package on the corner of a baking sheet. Then spread out the pumpkin chunks on the remainder of the baking sheet ensuring the pieces do not touch. This ensures they will caramelize and get crispy.
Bake beets and pumpkin until they are easily pierced by a fork or knife, 45 minutes to 1 hour depending on size. After 20 minutes, flip pumpkin chunks so they bake evenly on both sides.
Meanwhile, in a large bowl, combine minced garlic, oil, vinegar and sprinkle with salt and pepper to taste.
Remove roasted beets and pumpkin from oven and carefully open foil packages to let steam escape. Let cool at least 30 minutes.
Unwrap roasted beets and use a peeler to remove tough skin. Dice beets into bite-size pieces. Add to bowl with garlic mixture, mix well and let marinate in the refrigerator for 1 hour.
Moments before you're ready to serve get a large salad bowl and spread out chopped kale. Decorate with warm roasted pumpkin and marinated beets. Top with crumbled feta, pine nuts, roasted pumpkin seeds and fresh mint.
Drizzle salad with balsamic vinaigrette and serve warm or cold.