Using the Step 1 Ingredients, you’re going to do two things: make the caramel and warm-up the bourbon/water mixture to add once the caramel is done.
First, combine 3 tablespoons of water and the sugar into a small sauce pan and bring to a boil. Cook it without stirring (resist the temptation to mess with the pan). Let the caramel begin to pick-up color and simmer until golden in color. This should take 6-8 minutes. Don’t try to rush it.
While the caramel is simmering, warm the other tablespoon of water and the two tablespoons of bourbon in another pan just enough to warm through.
When the caramel is ready, remove it from the heat and slowly pour the bourbon/water mixture into the caramel swirling the caramel to combine.
Immediately pour into 4 6oz ramekins.
Using Step 2 Ingredients, make the custard by combining the eggs in a large bowl until well beaten. Add the remaining ingredients and whisk until smooth. If you want to make sure the custard comes out perfectly smooth, pass the mixture through a sieve before ladling into the prepared ramekins.
Place the ramekins into a shallow baking dish or pan and fill it with enough hot water to come half-way up the sides of the ramekins. (The French call this a bain-marie, which is basically a hot water bath that helps gently distribute the heat when cooking delicate things like custards). Transfer the pan to the oven and bake at 325℉ for 40-45 minutes. Keep an eye on the flan and remove when it is just set but still jiggles a bit when you tap it.
Remove the ramekins from the pan, cool to room temperature and then cover and refrigerate overnight.
To serve, run a knife along the edge of the flan to loosen it from the sides. Put the ramekins into a pan with about ¼” hot water for about half a minute (to loosen the caramel), then turn over onto a serving plate. Drizzle any remaining caramel over the flan and serve.