In a large bowl with an electric mixer on medium speed, cream butter, shortening, brown sugar, and granulated sugar until light and fluffy, about 3 minutes. Add eggs, one at a time, beating well after each addition. Beat in vanilla. Scrape down sides of bowl.
1/2 cup unsalted butter, 1/2 cup vegetable shortening, 225 grams dark brown sugar, 156 grams granulated sugar, 2 eggs, 2 teaspoons vanilla extract
On low speed or using a wooden spoon, gradually add flour mixture, beating just until blended. By hand, fold in the chocolate chips.
1 1/2 cups chopped semisweet chocolate or semisweet chocolate chips
Using a tablespoon cookie scoop, scoop the dough and drop the balls about 2 inches apart on prepared cookie sheets. Bake one sheet at a time in a preheated oven for 10-12 minutes, or until edges start to turn lightly golden brown. Place the remaining dough into the fridge while the first batch of cookies bake.
Cool your cookie sheet before adding another batch of cookies to it. When it’s winter time, I find it rather easy to place the cookie sheet outside. I use two large sheets, that way while one is cooling, the other can go in the oven.
Immediately slide parchment paper onto a wire cooling rack. Cool cookies for 5 minutes, then transfer off the parchment paper to the cooling rack to cool completely.
I used a combination of 130g of semi-sweet chips and 110g (4 oz) of a bar of bakers chocolate, chopped.
Take the butter out of the fridge while you prep your other ingredients. Then slice it into tablespoons just before incorporating. The butter does not need to be overly softened for this recipe, so there's no need to let it rest until it's completely at room temperature (please do not microwave it).
I always take my eggs out when I take the butter out. Crack them into a bowl and allow them to rest at room temp with the butter while you prep the other ingredients.
I highly recommend using a kitchen scale for the most accurate weight. If you do not own a scale, use the scoop and sweep method. Aerate the flour with a spoon then scoop the flour using the spoon into the measuring cup until slightly overflowing. Gently level the flour by sweeping off excess using the back end of a butter knife. Too much flour will result in dry, crumbly cookies, and too little flour will yield crisp, flat cookies.