For the cake:
1 package boxed yellow cake mix
1 package (3 oz.) Lemon Jello
4 large eggs
3/4 cup vegetable oil
3/4 cup water
Beat all ingredients together for 10 minutes. Bake at 375 degrees for 30-35 minutes in a greased 13x9 inch pan. When done immediately punch full of holes with a large serving fork (I used a meat fork) all the way to the bottom of pan. Pour icing over immediately.
For the Icing:
Make ahead while cake is baking
1 cup fresh lemon juice
5 cups powdered sugar
In a saucepan over medium-low heat mix together the lemon juice and powdered sugar until melted and warm. Pour icing over hot cake immediately and broil until icing bubbles, watch carefully, you just want it bubbly, not browned too much.
For the Meringue:
7 large egg whites
1 3/4 cups sugar
1/2 teaspoon cream of tartar
1 Tablespoon plus 1 teaspoon amaretto liqueur
Whisk the egg whites and sugar together in a nonreactive metal bowl until combined. Set the bowl over a saucepan of simmering water. Cook, whisking constantly, until the sugar is completely dissolved and the mixture registers to 140 degrees F. on an instant-read thermometer, 6 to 8 minutes.
Remove the bowl from the pan and, with an electric mixer fitted with the whisk attachment, beat the mixture on high speed until stiff peaks form, adding the cream of tartar when the mixture begins to thicken or after 3 minutes. When the mixture almost holds stiff peaks, after about 6 minutes, add the liqueur and beat to incorporate it. Spread meringue on top of cake and form peaks with spatula. Place under broiler for a few minutes. Watch carefully, browns quickly.