To cook any winter squash into a puree, seed and peel it and cut the flesh into pieces. Simmer the squash in a heavy-bottomed pot with about 1-inch of water and a little salt, tightly covered, until it is falling apart. Lift the lid and give it a stir now and then, adding a little water if necessary. When the squash is completely tender, remove the lid, raise the heat, and stir constantly as you cook away all the excess moisture. Then mash the pulp with a potato masher or puree it in a food processor. The finished product should have the consistency of thick applesauce.

Heat the milk in a medium-sized saucepan and whisk in the semolina, cornmeal, and 2 teaspoons of butter. Continue stirring with a whisk or a wooden spoon until the mixture thickens, then remove it from the heat, let it cool for about 5 minutes, and whisk in the beaten eggs a little at a time.

Stir in the squash puree, the molasses, 1/2 tsp. Of salt, nutmeg, and cinnamon. Whisk all this together or process it in a blender for a few seconds - - the mixture should be silky smooth, with no lumps. Taste, and add more salt if needed.

Peel and quarter the onion and slice it rather thickly. Saute the onion in a tablespoon of butter with the ginger and a dash of salt until it begins to color. Lower the heat and keep cooking the onion until it is an even caramel color.

Stir the walnut pieces and the crumbled cheese gently into the squash mixture; the cheese should not get too mushy and blend into the custard, but rather should stay in distinct lumps. Pour the mixture into a large, shallow, buttered baking dish, and scatter the sauteed onions over the top. Put the flan into a preheated 400 oven; after 10 minutes, lower the heat to 350 and bake for 40 to 45 minutes more.

Serve the flan hot or warm, with some Simple Chipotle Sauce on the side.

To Make Simple Chipotle Sauce:

In a small non-reactive skillet, pour enough hot water over the chipotle chiles to cover them and let them soften for a few minutes, Take them out, pull out their stems and remove the main cluster of seeds, and return them to the skillet.

Cut the peeled tomatoes in wedges, and the onion into large chunks. Peel the garlic. Add the tomatoes, garlic, salt, and cilantro leaves to the chiles. Add a little more water if needed, just barely to cover the vegetables, and simmer it all for about 30 minutes.

Toast the cumin seeds lightly in a small pan, then grind them in a mortar and add them to the chile mixture. When everything is soft, puree the mixture in a blender. Taste, add a bit of salt if needed, and you're done.

Serve the sauce warm or cold, with quesadillas, with soup, with beans, with any kind of taco or enchilada, as a dip for tortilla chips, or with your morning eggs for a real wake-up call.

Makes 1 to 1-1/2 cups of sauce.