Easter Creme Egg® Rocky Road

Set out all the ingredients first. Measure the marshmallows, unwrap the chocolate eggs, and crush the biscuits.
Boil some water in a pot or a kettle and pour into a mug. Dip a sharp knife into the hot water for 1 minute. Remove the knife and wipe dry with paper towel. Use the hot knife to cut along the seam of 2 chocolate eggs, splitting them in half lengthwise. Leave 6 eggs whole.
Grease a 9-inch square baking pan. Line the bottom and sides with parchment paper, leaving an overhang on 2 sides. Randomly place 3 whole eggs on the bottom. Set aside.
Place condensed milk, chocolate, and butter in top of a double boiler over simmering water. Stir frequently, scraping down the sides with a rubber spatula to avoid scorching, until chocolate is melted and smooth, about 5 minutes.
Remove bowl from the heat and stir in marshmallows and biscuits until well combined. Transfer to the prepared pan, covering the three eggs on the bottom. Working quickly, add the 3 remaining whole eggs on top, along with the 4 egg halves. Sprinkle mini eggs on top. Refrigerate until chocolate is set, 1 to 2 hours.
Gently lift the rocky road out of the pan using the edges of the parchment paper. Place on a cutting board and use the hot knife method from step 2 to slice into squares. Cut through some of the whole eggs so you get the gooey centers oozing out of each slice.