Medium-sized zucchinis - about 10-12 - enough to cover the bottom of a large pot • ground beef (about 500 grams) • heaping tablespoons rice - I use this amount, but you can add more if you like • Butter - 1/2 cup (about 100 grams), I use fresh • large onion, finely chopped • Dill - finely chopped • Salt • Pepper • egg yolks for the egg-lemon sauce • lemon, depending on taste, I use half • Yogurt for serving