Three Layerd Jello

1.Spray a 9x13-inch pyrex pan with nonstick spray.
2.To make the first layer: In a medium bowl, mix one package of Jello with 1 envelope of the unflavored gelatin. Add 2 cups boiling water and stir to dissolve. Pour into the prepared pan. Refrigerate for about 30 minutes, or until quite firm.
3.To make the second layer: In another bowl, mix sweetened condensed milk with 1 cup boiling water. In a separate small bowl, sprinkle 2 envelopes of unflavored gelatin over ½ cup cold water. Let stand for a few minutes and then add ½ cup boiling water to dissolve the gelatin. Add to the milk mixture and stir to combine. Cool to room temperature. Pour the second layer over the firmed-up first layer. Refrigerate for at least 30 minutes, or until quite firm.
4.To make the third layer: In a medium bowl, mix the Jello with 1 envelope of the unflavored gelatin. Add 2 cups boiling water and stir to dissolve. Cool to room temperature and pour over the firmed-up second layer. Refrigerate for at least 30 minutes, or until firm.
5.Slice into individual servings, scoop out with a small spatula, and serve.