Preheat the oven to 350 degrees.
Peel the shallots, coat in olive oil, and put into foil. Peel tumeric and ginger and cut into thin slices. Arrange in a single layer, drizzle with oil, and wrap in foil. Pull the outer paper off the garlic. Cut the pointy tops off the heads of garlic so the cloves are partially exposed. Drizzle with oil.
Place all the foil packets on a baking sheet and bake for 15 minutes. Remove the ginger and tumeric. (it should be soft), increase the temperature to 400, and roast for 30 minutes until fragrant. When cooled, you can squeeze the garlic cloves out.
While the aromatics are roasting, pour boiling water over the chili peppers to rehydrate. Let them soak for 15 minute, and drain the water.
Pulse or puree until the yellow curry paste reaches your desired consistency. The recipe should make about 1 1/2 – 2 cups of curry paste. Use about 1/3 cup per curry recipe!