In a blender or food processor, grind the onion, garlic and ginger. In a skillet, heat up the vegetable oil on medium-low heat and add the onion mixture and cook while stirring for 5 minutes. Add to the skillet the spinach, cumin, cinnamon, clove, cayenne, yogurt and buttermilk. Turn the heat down to low and simmer uncovered for 20 minutes, stirring occasionally. Stir in the half and half and paneer cheese and simmer for 5 more minutes. Taste and adjust seasonings and add salt.
Meanwhile, to make the sauce, in a blender, puree the cilantro, mint, jalapeño, garlic, ginger, cumin, lemon juice and buttermilk until smooth (you will probably have to press down the sides of the blender with a spoon a couple of times to make sure all the herbs are pureed.). Stir the cilantro puree into the yogurt. Add salt to taste.
Preheat the oven to 350. Wrap the tortillas in foil and place in the oven for 10 minutes while the oven is preheating.
Grease a baking dish. Remove the tortillas from the oven and open the foil (be careful as there may be hot steam). Take a tortilla and spoon 1/4 cup of the filling down the center. Roll the tortilla and place seam side down in the baking dish. Repeat with remaining tortillas. Cover the tortillas with cilantro-mint sauce and bake uncovered for 5 minutes.
Serve topped with cilantro.
I recommend using whole-milk yogurt. And you can usually find paneer cheese at Whole Foods or Asian grocery stores such as Kalustyan in New York City.