Step 1

Combine the sugar and water in medium saucepan over medium heat.  Stir until the sugar dissolves (the liquid will 'clear up').

Step 2

Add the sliced strawberries and bring to a strong simmer (definitely don't let it boil), then reduce to low heat.  Cook (keeping a watchful eye!) on low for 12 minutes.

Step 3

Remove from the heat and add your mint leaves. Cover and let steep for 10 minutes.

Step 4

Strain the syrup carefully to remove the strawberries and mint leaves (it's probably still hot, so watch out for splashes), then let cool completely.  Store in an airtight glass container for up to 2 weeks (I can sometimes stretch it to 3).