2 spoons vinegar (optional)
Step 1. Wash strawberries in running water and place in a bowl of water with a spoon of vinegar.
Step 2. Rinse in running water and cut the tops off.
Step 3. Blend the strawberries to make a no-chunk jam.
Step 4. Add sugar and microwave for 30 minutes, leaving gaps to cool the jam after each 5 minutes.
Step 5. Place in a clean glass jar.
Step 6. Keep refrigerated upside down.