Preheat the oven to 350° F.
Line the baking sheet with a silicone mat or parchment paper.
In a medium bowl, whisk flour, baking soda, and salt together. Set aside.
In a stand mixer fitted with a paddle attachment or with a handheld electric mixer, cream the butter and oil at medium to high speed.
Beat butter and oil until well combined and smooth for about 2-3 minutes. Scrape down the sides of the bowl.
Add the sugar and vanilla and continue beating until the mixture is light, pale, and fluffy.
Scrape down the sides of the bowl.
Turn the mixer to low and add dry ingredients and milk; mix until fully combined.
Do not overmix.
Scrape the sides of the bowl and with a spatula or clean hands, bring the dough together.
If the dough is stiff and doesn't come together, add 2-3 teaspoon of more milk.
Do not knead the dough.
Scoop the dough with an ice cream scoop and roll it into a ball.
Flatten the balls with the palm of your hand and place them on a baking sheet keeping them 2 inches apart.
Bake in the preheated oven for 14-16 minutes or until the cookies are lightly golden around the edges.
Remove the cookies from the oven and allow them to cool on the baking sheet for 4-5 minutes.
Transfer the cookies onto a wire rack and allow them to cool completely.