Preheat the oven to 350°F. Cut the red cabbage into slices about 3/4 inch thick across the width. Place them on a baking sheet lined with parchment paper. In a bowl, mix the olive oil and salt. Finely grate the lemon zest into the bowl, then squeeze the juice and add it along with the cumin and pepper. Press the garlic over the mixture and mix well. Spread over the cabbage steaks, bake for 30-40 minutes, depending on the thickness of the slices.