Give it a twist
Use peaches, nectarines or apricots instead of plums, or replace rosemary with lavender.
Serve with yogurt instead of ice cream, for a healthier alternative.
Put the sugars into a saucepan with 250ml/9fl oz cold water. Heat gently and stir until the sugars have dissolved, then bring to the boil and simmer for 10 mins to reduce slightly.
Add the lemon zest and juice, rosemary and plum halves, bring back to a simmer and cook gently for 10 mins until the plums start to soften. Tip the blackberries into the pan and stir gently to warm through. Serve in bowls with scoops of ice cream.