Make the Pound Cake:
Pre-heat oven to 350F and spray a 9×5-inch loaf pan with floured cooking spray, or grease and flour the pan; set aside.
To the bowl of a stand mixer fitted with the paddle attachment (or large mixing bowl and electric mixer) , add the I Can’t Believe It’s Not Butter!® Spread, sugar, and beat until light and fluffy, about 3 minutes.
Stop, scrape down the sides of the bowl and with the mixer running on low speed, add the eggs one at a time, beating well after each addition.
Add the lemon extract and beat to incorporate.
Stop, scrape down the sides of the bowl, and add 1 1/2 cups flour, baking powder, optional salt, and beat on low until just incorporated, about 1 minute; don’t overmix.
Add the lemon zest and beat on low to incorporate.
Turn half the batter out into prepared pan; setting pan and remaining batter aside. (In the steps below, you’re layering in half the batter, half the blueberries, remaining half of the batter, remaining half of blueberries. This helps prevent the blueberries from sinking to the bottom, prevents the entire batter from turning blue-green-gray, and provides a visual appeal of berries on top of cake.)
To a small bowl, add the blueberries, sprinkle with 1 tablespoon flour, and toss with your fingers or a spoon to coat. Flouring the blueberries helps prevent sinking while baking.
Evenly sprinkle half the blueberries over the batter in the pan.
Top with remaining batter.
Top with remaining blueberries.
Bake for about 70 to 75 minutes (I used frozen and baked 74 minutes; baking time will likely be less if using fresh berries), or until a toothpick inserted in the center crack comes out clean or with a few moist crumbs, but no batter. At the 60-minute mark, I recommend tenting the pan with a sheet of foil (loosely drape a sheet of foil over pan) to prevent the top and sides from over-browning before the center fully cooks through.
Allow cake to cool in pan on a wire rack for about 15 minutes before turning it out to cool completely on a rack before glazing. While cake cools, make the glaze.
Make the Glaze:
To a small bowl, add the lemon juice, confectioners’ sugar, and whisk until smooth and combined, noting you may have to play with the sugar (or lemon juice) amounts slightly to achieve desired glaze consistency.
Evenly (and liberally; I used much more than the photos show) drizzle glaze over bread before slicing and serving.