Air Fryer Oven Brownies

Grease and flour an 8x8-inch square pan.

Sift flour, baking powder, and salt together in a bowl.

Beat sugar and butter together in a large bowl with an electric mixer until light and fluffy. Beat in eggs until a smooth batter forms. Beat in chocolate and vanilla extract. Stir in the flour mixture until just incorporated; fold in walnuts. Spread batter into the prepared square pan.

Place pan in the air fryer basket. Place on the lowest rack in air fryer oven and cook at 300 degrees F (150 degrees C) until a toothpick inserted in center comes out clean, 18 to 25 minutes.

Cool completely in the pan, about 30 minutes. Cut into 9 squares and sprinkle with powdered sugar.