I didn’t have any milk at home but needed to bake something for our work potluck so I found this recipe substituting soy milk for cow’s milk. You can find the original posting here but here it is as well (with a few modifications, like I doubled the recipe for a thicker flan):
1 cup granulated sugar (used 1/2 only)
1/4 cup water (used 1/2 only)
2 cups soy milk (used vanilla soy milk so left out the vanilla extract)
1 teaspoon vanilla extract (did not use)
2 egg yolks
1 pinch salt
1/2 cup sugar (used 1/2 only since soy milk a bit sweetened)
1. You can use a loaf pan and make one large flan (I made one large pan) or smaller ramekins. Six 6-ounce ramekins or 4 larger ones work well for this recipe. Preheat the oven to 300 degrees. Put water on to boil.
2. Combine sugar and water in a small saucepan over low heat until sugar melts and mixture begins to darken. Stir occasionally. When the sugar mixture turns a dark golden brown – this will take about 15 minutes. Remove from the heat and pour enough to coat the bottom into each ramekin, if using, or pour all into the bottom of the loaf pan.
3. Heat the soy milk and the vanilla in a small saucepan until it is just about to boil. Turn off burner and put aside.
4. Beat eggs, egg yolks, salt and sugar in a bowl with a whisk (or using an electric mixer) until they are a light yellow color.
5. Stirring constantly, pour the milk mixture in a thin stream into the egg mixture until they are completely combined. Pour into loaf pan or divide equally among the ramekins.
6. Put the loaf pan or the ramekins into a deep roasting dish and put it on the middle shelf in the oven. Pour boiling water into the roasting dish until the water comes about halfway up the sides of the custard dishes.
7. Bake for about 45 minutes to 1 hour or until the the custard is almost set, but the middles are still wiggly. Remove from oven and let cool. Refrigerate until you are ready to eat them.
8. To serve flan, place ramekin (or loaf pan) into hot water for 20 seconds, run a thin sharp knife around the edge of the dish and invert it onto a dessert plate.
One other modification on cooking time, I baked it at 300 F for 60 minutes and the center was still quite jiggly so turned up the heat to 325 F for another 30 minutes, still jiggly, so finally turned it up to 350 F for another 30 minutes before it finally solidified to my satisfaction. I cooled it overnight in the refrigerator and served it in the dish (did not invert it onto a dessert plate).
When you cut into it though, the caramel gets all over the place (see the thick layer on the bottom).
I think if I make it again and use the vanilla soy milk, I would completely cut out the granulated sugar. It’s plenty sweet and the caramel does the job. My co-workers said it tasted good (they couldn’t tell it was soy milk) and the texture was between JELL-O and flan, thicker than flan but not as thick as JELL-O.