Preheat the oven to 375. Line a muffin tin with papers and set aside.
In a medium bowl, add the flour, sugar, baking powder, cinnamon and salt and whisk to combine. Make a well in the center and set aside.
In another bowl add the yogurt, strawberry pieces, butter, milk and egg and whisk to combine. Pour into the well in the flour mixture and using a scraper/spatula, lightly mix the wet into the dry until just combined.
Drop one tablespoon of batter into the prepared muffin cups and top with 1 teaspoon of jam. Top evenly with the remaining batter.
In a small bowl, combine the 1 tbsp of sugar and 1/2 tsp cinnamon and sprinkle evenly over the tops of each muffin. Bake for 15 minutes, or until centers are done. Cool for 10-15 minutes before serving.
Notes
Note: you could change this recipe by adding different flavored yogurts or jam. Blueberry or Blackberry would be outstanding.