2 cups (8.5 ounces, 241 g) unbleached all purpose flour
1 cup (3.5 ounces, 99g) old-fashioned oats
1 teaspoon baking powder
1 teaspoon baking soda
1 teaspoon Kosher salt or ¾ teaspoon regular table salt
1 cup (2 sticks, 8 ounces, 227 g) unsalted butter, room temperature
1 cup packed (7.5 ounces, 213 g) light brown sugar
½ cup (3.5 ounces, 99 g) granulated sugar
1 large egg, room temperature
1 large egg yolk, room temperature
1 Tablespoon vanilla extract
2 cups (12 ounces, 340 g) bittersweet chocolate chips
1 cup (6 ounces, 170 g) toasted pecan pieces*

Preheat oven to 325° F.  Line a baking sheet with parchment paper.

Whisk together the flour, oats, baking powder, baking soda and salt.  Set aside

Beat together the butter and sugars until smooth.  Add the egg, egg yolk and vanilla one at a time, betting well after each addition.

Add flour mixture; mix until everything is thoroughly incorporated.  Scrape the bottom and sides of the bowl and mix briefly.

Stir in the chocolate chips and pecan pieces.

Using a 1½-inch disher, scoop the dough onto the prepared baking sheets, leaving about 1½ to 2-inches between the cookies.

Bake at 325° F for 12 to 15 minutes, or until the cookies are a light golden brown, with slightly darker edges.  Remove cookies from oven and let cool for 5 minutes on baking sheet.  Remove to wire rack to cool completely.  Yield:  4 dozen cookies.