With an electric mixer, beat egg yolks and sugar 3 to 4 minutes until thick and lemon colored. Set the whites aside. Whisk the yogurt, milk, lemon extract, and lemon zest into the egg yolk mixture. Sift the dry ingredients into a bowl and reserve. Using clean beaters, beat the egg whites until they form stiff peaks. Whisk the dry ingredients into the liquid just until smooth. Fold in the egg whites.
Cook pancakes on preheated greased griddle until top bubbles, flip gently, and cook about 1 more minute. Make 3 to 4 inch pancakes. Do not overcook; they should be lightly browned. Wash flower petals thoroughly. Make sure there are no bugs hiding in your flowers. Pull apart flower petals into small pieces. Fold into batter.
Wash and clean stems from berries. Warm the fresh berries in a saucepan on low heat with a little sugar until the berries throw off their liquid. Add a few drops of water if needed. Frozen blueberries may be used; heat frozen berries and add a little lemon juice if they are too sweet. Thicken with cornstarch if needed.
Put lemon slice on plate, place a dollop of freshly whipped cream on top of lemon slice, then with scissors cut tiny pieces of edible flower petals used in pancake over the whipped cream. Stick a leaf of lemon verbena or lemon balm in whipped cream for additional garnish. You may add a whole flower on the side. Enjoy!