Preheat oven to 350º.
Mix cookie crumbs and butter till blended.
Press crumbs onto bottom and 1-inch up sides of 9 inch springform pan or removable bottom pan. Refrigerate while preparing filling.
In a mixer, with the paddle attachment, beat cream cheese until fluffy.
Add 1 cup sour cream, 1 cup sugar, Grand Marnier, tequila, lime juice and lime zest and beat until well blended.
Add eggs 1 at a time, beating just until blended.
Remove bowl from mixer and use spatula scrape bowl to make sure batter is well mixed.
Pour filling into crust.
Bake until center is just set, about 50-55 minutes.
Mix remaining 1 cup sour cream, ¼ cup sugar and 1 tablespoon lime juice in small bowl.
Pour over cheesecake and carefully smooth with a spatula.
Bake cheesecake for 5 more minutes.
Place pan on rack and cool to room temperature.
Refrigerate until well chilled, at least 4 hours or overnight.
Remove from pan and garnish.
