Preheat the oven to 350°F; spray a loaf pans with nonstick spray.
In a large bowl, sift together ¾ cup of sugar, flour, baking powder, and salt.
Add egg substitute, oil, egg yolk, lemon zest, and vanilla to the bowl. Use a whisk to mix until smooth.
In a different bowl, use an electric mixer on medium-high speed to beat the egg whites until they are thick.
While still mixing, slowly add ¼ cup of sugar. Continue to beat until you see stiff, shiny peaks form.
Take a rubber spatula and gently fold about one-third of the beaten egg whites into the flour mixture. Mix well.
Fold in the rest of the egg whites.
Pour the mixture into the prepared pan.
Bake for about 30 minutes or until a toothpick inserted into the center comes out clean.
Let the cake cool in the pan on a rack for 10 minutes, then remove it from the pan onto the rack.
In a small saucepan over medium heat, mix the lemon juice and the remaining 6 tablespoons of sugar. Stir constantly until the sugar is fully dissolved, about 2 minutes.
Pour the lemon-sugar mixture over the cake.
Allow the cake to cool completely before serving.
Notes
7 Points (2022/2024 Plan)MyWW Points: 7 Blue Plan and 6 Green Plan7 WW Freestyle Points and 6 Smart PointsWe are not associated with Weight Watchers/WW in any way. Double check points on their official calculator.