If baking the crust, preheat oven to 375 degrees F. Line an 8x8 baking pan with aluminum foil; lightly butter (or use cooking spray) the bottom and sides. Set aside.
Combine crumbs and 3 Tablespoons sugar in a medium bowl. Add butter and mix well, until clumps start to form. Press crumbs firmly on bottom and up sides of prepared pan. Either bake for 8-10 minutes and cool completely, or chill in the refrigerator for at least an hour before filling.
To make the cheesecake filling, beat cream cheese in a large bowl on high until smooth and fluffy. Add remaining sugar in gradually, beating constantly. Blend in salt, milk, lemon juice, and vanilla, beating until well combined.
Fold in whipped cream, or blend in on low speed until fully combined. Spoon filling into cooled crust and spread evenly. Refrigerate 3-4 hours until set. Cut into squares. Garnish with quartered lemon slice and mint leaf, serve, and enjoy!