Preheat oven to 325 and position oven rack in the lower third of the oven. Spray a bread pan with cooking spray and flour or use Pam Baking Spray.
Sift together flour and baking soda; set aside. In a bowl, beat butter and cream cheese on medium until creamy. Gradually add 1 ½ cups sugar; beat until light and fluffy, about 5 minutes.
Increase speed to medium-high; gradually add egg substitute, beating well. Beat in vanilla and 2 tbsp lemon juice.
Reduce speed to low; add flour mixture in 3 additions until mixed well. Fold in lemon zest.
Spoon batter into prepared pan. Bake until a toothpick inserted into the center comes out clean, about 70-75 minutes. Let cool on a wire rack for about 15 minutes.
In a small saucepan over medium heat, whisk 3 tbsp lemon juice and ¼ cup sugar until sugar is dissolved.
Turn cake out onto waxed paper or serving plate and brush with glaze. Let cool completely. Cut into 12 slices.
