Preheat oven to 375 degrees. Toss sweet potatoes in olive oil, 1/4 teaspoon of the salt, and 1/8 teaspoon pepper. Spread on a parchment-lined or nonstick baking sheet.
Roast for 25 minutes, flipping the pieces halfway through, or until fork-tender and browned a bit.
Add kale, tomatoes, sweet potatoes, remaining 1/4 teaspoon salt, and 1/8 teaspoon black pepper to a salad bowl and toss. Sweet potato pieces may be added warm or cool. Sprinkle the salad with sesame seeds and pumpkin seeds or sunflower seeds.
Gently toss avocado slices in lemon/lime juice, and add on top of the salad. Enjoy with your favorite dressing or a simple vinaigrette.