In a large bowl, sift together the flour and salt. Stir in the dry milk, sugar, and yeast.

Make a well in the center and add the lukewarm water and oil. Stir with a wooden spoon until the dough begins to come together.

Add the poppy seeds and knead by hand until fully incorporated and the dough pulls away from the bowl.

Turn the dough out onto a lightly floured surface and knead for about 10 minutes, until smooth and elastic.

Lightly oil a clean bowl, place the dough inside, and turn to coat. Cover and let rise in a warm place for 1 hour, or until doubled in size.

Punch down the dough and knead briefly. Divide into three equal pieces and roll each into a rope about 10–12 inches long.

Place the ropes side by side, pinch together at one end, and braid. Pinch the other end together and tuck underneath.

Transfer the loaf to a lightly oiled baking sheet. Cover and let rise for 30 minutes.

Preheat the oven to 400°F (200°C).

Whisk together the egg yolk, milk, and sugar. Brush over the loaf and sprinkle with poppy seeds.

Bake for 30–35 minutes, until golden brown and the loaf sounds hollow when tapped.

Transfer to a wire rack and cool before slicing.