In a small bowl, sprinkle yeast over the lukewarm milk. Stir to combine and let sit until frothy, about 10 minutes.
In the bowl of a stand mixer fitted with a dough hook or a large bowl, combine 3 cups (375 grams) of the flour, the sugar, and salt.
Mix in the milk with yeast, butter, and egg. Slowly add the remaining 1 cup (125 grams) flour to bring together a soft and slightly sticky, workable dough. If too dry, add a little more milk. Be careful to only add as much flour as needed. Too much will create tough rolls.
On a lightly floured surface, knead dough until smooth and elastic. Place in an oiled large bowl, turn to coat, and cover. Allow to rest until doubled in size, 1-2 hours.
Place the bread crumbs in a shallow bowl. Lightly grease a 9x13 inch (23x33 centimeter) rimmed baking sheet or pan.
On a lightly floured surface, divide the dough into 20 equal pieces. Form each piece into a ball and roll in the breadcrumbs to coat. Place on the prepared baking sheet 1 inch (2.5 centimeters) apart. Repeat with remaining dough.
Cover with a towel and let rise until puffed, 30 minutes to 1 hour.
While rising, preheat oven to 350˚F (180˚C). Bake the rolls until soft and golden on the top, about 20 minutes.
Serve warm from the oven plain or with desired fillings.