Soak panko breadcrumbs in whole milk for about 5 minutes until absorbed.

In a large bowl, combine soaked breadcrumbs with the egg, grated garlic, salt, pepper, nutmeg, allspice, and ground beef. Mix gently until well combined.

Form the mixture into meatballs using a cookie scoop.

In a skillet over medium heat, melt 1 tablespoon of butter and sauté frozen pierogies until golden brown; set aside.

In the same skillet, add olive oil and sear meatballs until golden brown; transfer to a plate.

Melt remaining butter in the skillet and sauté onions until soft. Stir in flour for about 2 minutes.

Gradually whisk in beef broth and milk; cook until thickened.

Return meatballs and pierogies to the skillet; stir gently until heated through.

Serve warm garnished with fresh parsley or dill.