Preheat oven to 325 degrees. Place 6 - 6 oz. ramekins in a 9 x 13 inch baking pan.
Place granulated sugar, water and lemon juice in a medium saucepan, bring to a gentle boil over medium-high heat.
Continue to cook for 6 minutes or until the syrup turns from clear to golden, swirling pan gently.
Continue to cook for another 2 minutes or until it turns to a honey-caramel color.
Immediately pour caramel evenly into each ramekin.
Cool for about 15 minutes or until caramel has hardened.
Place evaporated milk and brown sugar in a medium saucepan. Bring to a gentle boil over medium heat. Cook, stirring frequently until sugar is dissolved.
Whisk together pumpkin, eggs, egg yolk, vanilla extract and orange peel in medium bowl until well incorporated. Slowly whisk hot evaporated milk mixture into egg mixture. Using a sieve, strain the custard into a glass measuring cup (this will guarantee a velvety-smooth texture).
Pour mixture into prepared ramekins. Add enough hot water to the baking pan to reach halfway up the ramekins.
Bake for 55 minutes or until custard is just set (centers should be slightly jiggley). Transfer ramekins to a wire rack, cool until cold enough to cover and refrigerate.
Refrigerate for 3 hours or until completely cold.
To serve, run knife around the inside perimeter of ramekins. Invert onto serving plate.