Pre-heat your oven to 100ºC/80ºC fan.
Line your baking sheet with baking parchment or bake-o-glide sheet.
Put your egg whites (2 large egg whites) into a large bowl and beat on a low speed until foamy. Increase the speed to medium and beat until they form a soft peak.
With your mixer still running, add the caster sugar (100g) a tablespoon at a time and whisk until combined. Continue to beat until you have a stiff peak.
Add the orange oil (¼ tsp) and carefully fold into the meringue mixture until fully combined.
Attach the nozzle to your piping bag and fill the piping bag with the meringue. Pipe your meringue roses onto the baking sheet (if you need guidance on how to do this have a look at this video).
Place into the oven and cook for 1 hour 45 minutes. Once cooked turn off the oven but don't open it. Leave the meringues in until the oven has cooled completely (this can take several hours).
Once the oven has cooled completely remove the meringues and either use them immediately or store them in an airtight container to use later.