Wash the orange. Cut off the bottom and top of the orange. Cut the peel and white skin vertically from one end to other, without taking the fruit.
Cut the pieces into 1/4(6mm),1/3 (8mm) thick.
Blanching: Put the peels in pan and cover with enough water and bring to a boil. Remove the peels from the pan and drain. Cover the pan with fresh water and repeat this process 2 more times to remove the bitter taste of the skin.
Place the water and sugar in a medium pan over med-low heat and stir until the sugar dissolves. Let it simmer.
When the sugar simmers, add the orange peels and lemon juice to avoid crystallization. Let the mixture simmer without stirring for 25 to 30 minutes at low heat until the peels become almost translucent and syrup thickens.
Place the candied peels on a wire rack using a fork or tongs. Let them cool at room temperature. If you want the peels to dry completely, you should wait at least 24 hours. If a slight stickiness is fine, a couple of hours will be enough.
Melt the chocolate over bain-marie: Place the chopped chocolate into a heatproof bowl that sits over a pan of simmering water. Stir often. Remove the bowl from the heat when melted. Alternatively, you can melt the chocolate in the oven at 210°F (100°C) by placing the chopped chocolate into a heatproof bowl. You should check the oven often and stir when it starts to melt. If there are some pieces not melted, continue melting in the oven and stir again.
When the chocolate melts, dip half of the peels or whole peels into the melted chocolate and place them on a parchment paper. You can keep the candied peels in an airtight container up to a month. (If you like, you can toss the peels with sugar instead of dipping into melted chocolate before the peels dry completely.)
*90 grams (3 oz) of chocolate is more than needed if you dip half of the peels but it makes it easier to dip.