For the pudding: Preheat oven to 350°F. Add butter to skillet and sweat onions for 3 minutes. Stir in jalapeño; add corn kernels and herbs. Heat this corn mixture in a skillet over medium-high heat, and then reduce to a simmer. Add whipping cream to skillet and simmer 5 to 7 minutes, or until slightly thickened, to make creamed corn. Remove from heat to cool slightly.
In a medium-size mixing bowl, beat eggs and then add milk. Slowly whisk in cornmeal, sugar and then the ricotta. Ladle and stir the cooked creamed corn into the egg mixture. Season with salt and pepper. Spray and coat a 10- to 12-cup cast-iron skillet or casserole dish, and then pour in the pudding mixture. Add freshly grated nutmeg over top.
Bake 35 to 40 minutes — until top begins to brown — and you can insert a toothpick into the center and it comes out clean. Let rest 5 minutes. Serve warm.