Pumpkin Flan with Maple Caramel

For the caramel:

¾ cup sugar

1/3 cup pure Grade A maple syrup

½ teaspoon fleur de sel

For the pumpkin flan:

1 (14-ounce) can sweetened condensed milk

1 (12-ounce) can evaporated milk

1 cup canned pumpkin puree (not pie filling)

½ cup (4 ounces) Italian mascarpone

4 extra-large eggs

1 teaspoon pure vanilla extract

½ teaspoon pure maple extract

2 teaspoons grated orange zest (2 oranges)

1½ teaspoons ground cinnamon

½ teaspoon ground nutmeg