Pre-heat oven to 450 degrees on broil. Slice approx. 2/3 of the fresh leek into thin slices. Halve those slices. Cut each baby new red potatoes into six pieces. Quarter the artichoke hearts and set aside. Add butter, leeks, baby potatoes, and fresh rosemary to a 12" skillet. Cook uncovered until slightly browned and potatoes softened. Add artichokes, fresh cilantro, salt, pepper, and beau monde. Cook for additional 4-5 minutes.
Beat fresh eggs and milk well with hand whisk until slightly frothy. Spread the artichoke, leek, potato mixture evenly on the bottom of the skillet. Add the egg mixture to the skillet. Continue cooking until egg mixture begins to slightly solidify on the top.
Add the parmesan cheese to the top of the frittata followed by the shredded four-cheese blend or mozzarella.
Transfer skillet to the oven. Broil until top of frittata turns golden brown. Cut into six wedges and serve with sprig of fresh rosemary inserted at angle into top.