In a medium bowl- combine all-purpose flour, cinnamon, ginger, baking soda, salt and whisk to combine.
In a stand mixer fitted with a paddle attachment- beat butter and brown sugar on medium speed for 2-3 minutes or until light and creamy. Scrape down the sides of the bowl. Add egg and beat on medium speed for 1 minute, add molasses and beat on medium speed for 1 minute. Add sweetened condensed milk and beat until combined.
Add dry ingredients to wet ingredients and mix on low speed for 30 seconds- careful to not over mix the batter. Batter will be sticky. Cover the mixing bowl with plastic wrap and chill dough in the refrigerator for 30 min-1 hour or overnight.
Preheat the oven to 350°F degrees. Line 2 baking sheets with parchment paper. Set aside.
Using a cookie scoop or two spoons, scoop cookie batter into 2 inch round balls. Dough will be sticky. Sprinkle top with turbinado sugar and bake for 10-12 minutes. Allow to cool on a cookie sheet for 10 minutes before serving.