In a large mixing bowl, cream together 1 cup of softened butter, 3.4 oz of instant pistachio pudding mix, and 1 cup of sugar until light and fluffy, about 2-3 minutes. Beat in 2 eggs, 1 tsp of vanilla extract, and ½ tsp of almond extract until fully incorporated. Gradually mix in 2 cups of all-purpose flour, 1 tsp of baking powder, and a pinch of salt, stirring just until the dough comes together.

Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan. Press the prepared dough into the bottom of the pan. Bake for about 20 minutes, until the edges are lightly golden and the center is set. Let cool completely.

In a separate bowl, beat together 8 oz of softened cream cheese and ½ cup of soft butter until creamy. Gradually mix in 2 cups of powdered sugar followed by 1 tsp of vanilla extract and optionally, ½ tsp of almond extract until velvety.

Spread the cream cheese frosting evenly over the cooled bars. Optionally, sprinkle chopped pistachios on top for garnish. Let set for a few minutes before cutting into squares.

Serve at room temperature. Store leftovers in an airtight container for up to four days.