In a large bowl, whisk together flour, baking soda and salt. Set aside.
In the large bowl of an electric mixer (or hand mixer) fitted with a whisk attachment, add butter, Stevia Organic Sweetener and vanilla. Beat for 4 minutes on medium-high speed, scraping down as needed, until fluffy and combined.
Add one egg. Beat for 1 minute or until well incorporated. Add the second egg and beat for a further 1 minute or until the mixture is pale and creamy.
Switch to a paddle beater (or use a wooden spoon - see notes). Add half of the flour mixture and beat for 1 minute on low speed until just incorporated. Add the remaining flour mixture and beat for another 1 minute or until the dough comes together.
Using a wooden spoon, fold in the milk and dark chocolate chips. Cover the bowl with cling wrap and refrigerate for 1 hour.
Meanwhile, preheat the oven to 160°C (fan-forced) or 180°C (standard). Grease and line two large cookie trays with baking paper.
Roll a tablespoon of dough into a ball and place on the prepared tray. Flatten slightly. Repeat with remaining dough.
Bake for 12 minutes or until light golden brown around the edges. Allow to cool on the tray for 10 minutes before transferring to a wire rack to cool completely.