Jell-O Preparation: Dissolve the lemon Jell-O in boiling water and set aside until it reaches a semi-solid consistency.
Crust Formation: Combine 3/4 of the graham cracker crumbs with melted butter. Firmly press this mixture into the base of a 9x13-inch pan. Reserve the remaining crumbs for topping.
Creamy Texture: Whisk the chilled evaporated milk or heavy whipping cream until it forms soft peaks.
Cheesecake Mixture: In a different bowl, blend together cream cheese, granulated sugar, and lemon juice until it achieves a silky texture.
Combine & Fill: Mix in the semi-thickened Jell-O to the cream cheese mixture. Gradually fold in the whipped cream or evaporated milk.
Final Touch: Pour the entire blend over the previously prepared crust. Garnish with the leftover graham cracker crumbs.