Cut peel on each orange into 4 vertical segments. Remove each segment (leaving the white pith) in 1 piece. Cut into 1/4-inch-wide strips.

Bring 2 cups sugar and 3 cups water to boil in a medium saucepan over medium heat, stirring to dissolve sugar. Add peel. Reduce heat; simmer until peel is very soft, about 45 minutes to - 1 hour. Drain.

Toss peel and 1 cup sugar on a baking sheet, separating strips. Lift peel from sugar, transfer to a sheet of foil. Let stand until the coating is dry, 1 to 2 days.

When the peels are dry:

In a double boiler, over simmering water, melt the butter with the chocolate.

Dip half of the citrus peel, and place on parchment paper. place in refrigerator until the chocolate has hardened, about 30 minutes.

Keep refrigerated.