Preheat oven to 350. Line a sheet tray (18x13) with parchment paper.
Mix the flour, baking soda and salt together in medium bowl.
In stand mixer, beat butter and sugar together on medium high speed until fluffy and smooth. Add eggs and vanilla, beating until just combined. Slowly add the flour mixture with mixer on low speed and only mix until just combined.
Pour batter unto prepared sheet tray and evenly spread out with off-set spatula. Bake for 12-15 minutes.
Allow cookies to cool for about 20 minutes and then gently slide parchment paper onto an inverted sheet tray or large cutting board. Cut the bar in half. On one half off the cookie, evenly spread out your favorite ice cream (you could even through a few candies in the ice cream itself. Flip the other cookie half onto the half with the ice cream. Loosely wrap in plastic wrap or parchment and place into freezer for 1-2 hours until ice cream has hardened.
Using a very sharp knife, cut into 16 equal portions. Wrap the Ice Cream sandwiches up individually or layer with parchment paper in a food storage container. Keep frozen until ready to eat.