Preheat the oven to 400 degrees F. Grease an 8 cup oval gratin dish with 1 teaspoon of the butter.
In a large sauté pan, over medium heat, melt the remaining 2 tablespoons of the butter Add the onions. Season with salt and pepper. Sauté for 2 minutes. Add the flour and cook for 1 minute, stirring constantly. Stir in the milk and bring to a simmer. Cook for 4 to 6 minutes or until the mixture coats the back of a spoon. Add the peas and mix thoroughly.
Pour into the prepared pan. Season the bread crumbs with Essence. Sprinkle the bread crumb mixture over the peas. Top with the grated cheese.
Place in the oven and cook until the peas are bubbly and the top is golden, about 10 to 12 minutes.
Spoon onto serving plates and serve.
Yield: 4 to 6 servings