Ask for green, or unripe, strawberries at your local farm stand or farmers' market. Serve with a selection of Nordic cheeses and rye crackers.
Clean and dry a jar big enough to hold strawberries (at least 2 1/2 cups in capacity). Fill jar with strawberries, then add peppercorns, bay leaves, caraway seeds, and yellow mustard seeds.
Simmer vinegars, water, honey, and salt in a saucepan over medium heat until honey and salt are dissolved, about 8 minutes. Let cool completely. Pour mixture over strawberries to cover completely. Seal jar and give it a few gentle shakes. Refrigerate at least 12 hours, and serve within 2 days.