Line a rimmed baking sheet with parchment paper and set aside.

Slice oranges into 1/4-inch slices. Be sure to remove any seeds.

Combine sugar and water in a wide, large skillet. Over medium-high heat, bring the mixture to a boil, whisking until the sugar has dissolved.

Add orange slices in an even layer (you may need to cook the slices in batches depending on how big your skillet is). Bring the liquid to a simmer. Simmer for approximately 1 hour, uncovered. The orange slices should look transparent when they are done.

Remove orange slices to the prepared baking sheet. Let slices dry for at least 24 hours, uncovered. They will still be a little sticky at this point, and that's ok.

Place chocolate melting wafers in a bowl and melt in 10-15 second increments, stirring between each, until melted. You can also melt the chocolate in a double-boiler over medium-low heat if you prefer.

Once melted, dip each slice halfway into the chocolate and return to the parchment-lined baking sheet to set. Sprinkle with flaky salt right after dipping, if you are using it.

Repeat this dipping process until all slices have been dipped. Let set for at least 15 minutes, until the chocolate hardens, before serving or storing.