Preheat the oven to 350° F. Grease two loaf pans and line each with parchment paper.
In a medium-size mixing bowl, cream two cups of softened butter and two cups of sugar with a mixer on high speed for five minutes or until fluffy. Scrape down the sides of the bowl.
Reduce speed to medium and add one teaspoon of vanilla extract. Lightly beat in six eggs, one at a time mixing thoroughly after each and scraping down the sides of the bowl.
Reduce speed to low, and add three and one-quarter cups of Bisquick in two additions, mixing until just incorporated.
Fold two tablespoons of poppy seeds into the finished batter.
Divide batter between prepared pans and evenly smooth the tops of each. Bake for one hour, or until a toothpick inserted into the center of each cake comes out clean.
Let the cakes cool in pans on a wire rack for thirty minutes.
Remove from pans and let cool completely on a wire rack before applying the lemon glaze.
Combine six tablespoons of lemon juice and three-quarter cups of confectioner's sugar in a saucepan.
Bring to a boil, stirring constantly.
Boil for approximately five minutes or until the syrup has formed.
Allow the syrup to cool for five minutes before drizzling it over the cake.
Serve and enjoy.