In large skillet over medium heat, heat oil. Add garlic and sauté 1 minute. Add kale and cayenne pepper (if desired); salt and pepper to taste. Sauté until kale is wilted; remove from heat and set aside.
In large mixing bowl, combine yogurt, neufchâtel cheese and ½ cup Colby jack cheese; using an electric mixer on medium, mix until well combined.
Add kale, hearts of palm and green onions; salt and pepper to taste. Continue mixing until combined. Transfer to a greased 1-quart baking dish. Top with remaining ½ cup cheese.
Bake in a preheated 350°F oven 20-25 minutes or until bubbly. Serve with crackers.