In a medium mixing bowl, combine flour, salt, baking soda and cinnamon (if using). Set aside.
Add butter, sugar and brown sugar to a large mixing bowl and beat with an electric mixer until fluffy, about 5 minutes.
Add egg and vanilla and beat again until combined.
Add the dry ingredients and continue using the electric mixer until all ingredients are fully combined.
Stir in 1 cup of ruby chocolate chips.
Line baking sheet(s) with parchment paper and use a cookie scoop to drop 1.5 tbsp balls of dough onto the cookie sheet. Leave at least 3 inches of space between each cookie. Press extra ruby chips into the top of each dough ball using remaking 1/3 cup of chips if desired. You can also just mix them all straight into the dough.
Bake for 9-10 minutes, until golden brown on the edges. Top with sea salt and transfer to a wire rack to cool.