Stir the yeast into the warm milk, then add the flour and salt and knead until you get a smooth, elastic dough.
Cover the bowl with plastic wrap and place it in a warm oven for about 40 minutes. Knead the risen dough again, then let it rise a second time for another 30 minutes.
Turn the dough out onto a silicone mat and knead briefly, then cut the ball of dough into 2 equal pieces.
Cover one piece with plastic wrap so it does not dry out. Flatten the other piece into a rough rectangle, roll it up tightly into a log and pinch the seam well so the baguette does not open while baking.
Form the second baguette in the same way. Place both baguettes on a baking tray and let them rest for at least 20 minutes.
Brush the baguettes with the egg yolk mixed with a little milk, then use a sharp knife to make a few diagonal cuts on top.
Bake the baguettes in a preheated oven for about 30 minutes, until golden and crisp.
Serve the baguettes warm with tea and jam, or slice them and make sandwiches with salted red fish.