Heat a large skillet over medium-high heat. Add the butter and garlic, and cook until the garlic is fragrant, about 1 minute. Stir in the orzo, and thyme, and cook until golden and toasted, 2-3 minutes. Stir in the zucchini and kale, cooking another 2-3 minutes, until wilted. Add the 1/2 cup broth and de-glaze the pan. Add the lemon zest, lemon juice, onion powder and season with salt and pepper. Slowly continue to pour in the remaining 2 1/2 cups broth and bring to a boil over high heat. Simmer 8-10 minutes until the orzo is al dente, stirring often. It should become very creamy. Stir in the milk, parmesan, and parsley, cook another few minutes until warmed through. As the orzo thickens up on you, add additional broth to thin. It should be creamy, but with just a touch of liquid. Divide the orzo among bowls and top with fresh thyme...add additional butter...and parmesan, if desired. Hint? It's very desirable...