Preheat the oven to 350F. Grease a 9 x 13 pan and set aside.
Combine condensed milk and lime juice in a bowl, stirring until well combined. Note: a whisk will help, but you can achieve the same result using a spoon and some patience.
Put the gingersnaps in the bowl of a food processor fitted with a blade. Process (pulsing) until only small crumbs remain. Add oats and process for about 10 seconds, breaking the oats into smaller pieces. Add remaining dry ingredients and pulse till combined. With the blade of the processor running, drizzle in melted butter. Process until well combined.
Using about ⅔ of the crumb/crust mixture, create a cookie base by pressing firmly into prepared pan. Try to keep the cookie layer level for even filling.
Pour filling over base, using an offset spatula, rubber spatula or back of a spoon to spread it evenly.
Using remaining crumb/crust mixture, top the filling layer. NOTE: To create larger crumbs, simply squeeze mixture in your fist.
Bake at 350F for about 30 minutes, until golden brown and set. Let pan cool on a wire rack, then refrigerate for about an hour. Slice into pieces and ENJOY!