Start by combining 1 1/4 cups of sugar with 1 cup of water in a saucepan. Bring this mixture to a boil over medium-high heat. As the sugar dissolves, you’ll notice a sweet aroma filling your kitchen.
Once boiling, add the fresh rosemary sprigs to the syrup. Reduce the heat to a gentle simmer and allow it to cook for about 10 minutes. This step is crucial as it allows the rosemary to infuse its flavor into the syrup.
After 10 minutes, remove the saucepan from the heat and let the syrup cool. You can leave the rosemary sprigs to steep further, enhancing the flavor.
Next, take a sharp paring knife and carefully slice off the peel from each orange. Be sure to remove as much of the white pith as possible, as this can be bitter. Aim for clean, smooth slices.
Once peeled, slice each orange into thin ¼ inch rounds. Set these aside in a pie dish or similar container. Repeat this process until all oranges are prepared.
When the rosemary syrup has completely cooled, strain it through a wire mesh strainer to remove the sprigs. Pour the syrup generously over the sliced oranges.
If you’re using blood oranges, make sure to store them separately from the lighter oranges to prevent color bleeding.
Cover the dish with plastic wrap and refrigerate the orange slices for a minimum of 2 hours, or up to 2 days. This allows the flavors to meld and the oranges to absorb the sweet syrup.
Before serving, chop the pistachios finely. You want them to be somewhere between chunks and powder to create a lovely coarse meal.
Slice each date into thin strips. These will add a rich sweetness and pair well with the oranges.
To serve, arrange the chilled marinated orange slices on small dessert plates. Drizzle with 1 to 2 tablespoons of the rosemary syrup, just enough to moisten. Sprinkle with pistachios and top each slice with a date strip. Finally, garnish with a sprig of mint.