Pennsylvania Dutch Sticky Buns - adapted from the cookbook "The Lost Recipes" by Marion Cunningham. These can be frozen but should be served warm. The custard filling can be made while the buns are cooking. Prep time includes rising.
Dissolve yeast in warm water in a large mixing bowl and let dissolve for 5 minutes.
Put the milk and butter in a saucepan and heat until the butter is melted. Let cool to lukewarm.
Pour the cooled milk mixture over the yeast, then stir in the sugar, salt, eggs and 2 cups of the flour.
Beat briskly until well blended.
Add the remaining 2 1/2 cups flour and beat until smooth.
Cover the bowl and let the dough double in bulk. (At this point, if you want to leave the dough overnight, cover the bowl with plastic wrap and put it in the refrigerator.).
If you are proceeding immediately, when the dough has doubled in bulk, dust a work surface generously with flour and turn the dough onto it. (This is soft dough and needs enough flour on the work surface to prevent sticking.).
Pat the dough out in a circle if you are making round buns or into a square about 1/2 inh thick if you want square buns. (Use a biscuit cutter for round buns, and cut the dough into 2 1/2 inch squares for square buns.).
Preheat oven to 425°F.
Grease a baking sheet.
Cut out the buns and place them on the baking sheet, 1 inch apart. (They don't spread much, they rise.).
Let the buns rest and rise on the baking sheet for 20 minutes, uncovered.
Bake for about 10 minutes.
Remove and let cool a little.
Split only as many buns as you are going to serve and spread each with about 2 Tablespoons of the custard (at room temperature.).
Heat the milk in a heavy saucepan over medium-high heat until bubbles form a ring around the edge of the pan.
Mix the sugar, cornstarch and salt together in a bowl.
When the milk has formed bubbles, slowly pour it over the sugar mixture.
Stir briskly until smooth.
Pour the mixture back into the saucepan to cook over medium heat, stirring until thickened, or 3-5 minutes.
Taste the custard and if it is smooth, take it off the heat.
Add 1/2 cup of the custard to the eggs, stirring constantly for another 2 to 3 minutes.
When the custard is smooth, remove from the heat and add the butter and vanilla; stir to blend.
Let cool a little, cover and refrigerate until needed.