In a large bowl, toss vegetables with olive oil, thyme, 1 teaspoon salt and black pepper to taste. Preheat two heavy-duty baking pans in oven for 3 to 4 minutes. Carefully remove baking pans from oven and scatter vegetables on hot pans. Return to oven and roast, tossing vegetables a few times, until they are tender and a little caramelized, about 25 minutes.
While vegetables are roasting, toast cumin seeds in a small pan over medium heat, until seeds release their aroma, about 2 minutes. Using a mortar and pestle, pound cumin, then transfer to a small bowl. Repeat with coriander, toasting and pounding. Add coriander, butter, paprika and turmeric to cumin and stir to combine. In a small bowl, combine yogurt, lime juice, lime zest and a heaping 1/4 teaspoon of salt. Taste and adjust seasoning as necessary.
When vegetables are done, remove from oven. Combine vegetables in a single pan and toss in turnip greens and turmeric butter (the heat from the roasted vegetables will melt butter and wilt greens). Arrange vegetables on a platter. Top with kaffir lime yogurt and spoon mint chutney [see Recipe] over and around yogurt and vegetables, or pass yogurt and chutney at the table.
Nutrition information per each of 6 servings (without chutney):
Calories314Fat21 gSodium230 mg
Carbohydrates27 gSaturated fat6 gCalcium173 mg