Step 1
Preheat oven to 325 degrees F. Lightly spray 4 heatproof 6.5-oz. ramekins with vegetable spray. Place ramekins in a casserole dish.
Step 2
Place 1/2 cup sugar in a small heavy dry skillet over medium heat. When sugar begins to melt around the edges gently shake the pan continually swirling sugar around until all the sugar melts; don't use utensils to stir. When sugar is completely melted and dark brown remove the pan from heat.
Step 3
Quickly pour equal amounts of caramel syrup into the 4 prepared ramekins.
Step 4
Place 1 egg and 3 egg yolks in a bowl with a pinch of salt and 1/4 cup sugar. Whisk until sugar is dissolved and mixture becomes frothy about 1 minute.
Step 5
Spoon the creme fraiche into the egg mixture; add the milk vanilla and Grand Marnier. Whisk together until ingredients are completely mixed.
Step 6
Ladle mixture into the prepared ramekins filling them about 2/3 to 3/4 full.
Step 7
Fill casserole with hot tap water to reach halfway up the sides of the ramekins. Place casserole on middle rack of preheated oven.
Step 8
Bake until just barely set 45 to 50 minutes. You can start checking for doneness at about 40 minutes.
Step 9
Using tongs remove the ramekins from the casserole to a cooling rack. When just slightly warm run a sharp paring knife around the edge of each custard.
Step 9
To unmold cover ramekin with a small plate then invert. Chill before serving.