Line a baking tray with parchment or wax paper. This is important as the yogurt will stick to the pan if it is not lined.
In a bowl combine the yogurt and syrup. Pour onto the lined baking tray and spread evenly. Dot the strawberry jam in little mounds all over the bark. Use toothpicks to swirl. Dot with berries and sprinkle with chopped nuts.
Place in the freezer for at least 2 hours. Remove, break the bark into pieces and serve. The bark will keep in the freezer in an airtight container for 2 months.
This is a great recipe to make a day in advance. Allow the bark to sit in the freezer overnight.