In a dish with enough room for your bread to lie flat, whisk together your egg yolks, heavy cream, and a dash of vanilla. Give each piece of bread a good bath in this mixture, ensuring both sides get their fair share of soaking.
Now it's time to soak the bread in the mixture for a sweet spot between 30 minutes to an hour.
While those slices are soaking up flavor, go ahead and warm up your griddle to a nice medium heat. Patience is key—make sure it's just the right temperature before you introduce any bread to it.
If your griddle is non-stick, you might not need it, but a little butter can make everything better. Lightly grease your griddle. Then, lay those pre-soaked bread slices on it, cooking each side to a delicious golden brown. Just a single flip should do it. Or, if you're using a pan on the stovetop, you can achieve the same golden glory by frying each side in a bit of butter for about 4 minutes per side (making sure not to burn).
Keep those already done slices cozy and warm in a very low oven as you work through the entire batch.
For that final, irresistible touch, sprinkle a fine layer of sugar over each cooked slice of French toast. Use a torch to get that sugar nice and caramelized, watching as it turns golden and starts to bubble. If a torch isn't in your toolkit, no worries—lay them out on a baking sheet and pop them under the broiler for a similar golden sweet crust.