Preheat the oven to 300 degrees. Butter a loaf pan (8x4x2 1/4 inches).
In a large bowl, beat the eggs for 1 minute. Add the sugar and beat until blended. Stir in the milk and vanilla, and pour the mixture into the pan. Place the pan in a hot water bath and bake until it sets, about one and one-half hours. Remove from the oven, cool, refrigerate for 2 hours, and serve.
Makes 4 servings