Mushroom and cheese crostoni

These hot crostoni are delicious. You can make the cream ahead and keep it in the fridge, spreading it on the bread only when needed.
Ingredients for about 35 crostoni
250 g milk
150 g grated cheeses, such as Emmental, grana and Fontina
30 g dried mushrooms
15 g flour
15 g butter
Piquant Provolone, or mild if preferred
1 egg yolk
Salt and pepper
2 long loaves bread

I soak the mushrooms in lukewarm water, then squeeze them dry and chop finely.
I proceed as for béchamel: I melt the butter and add the flour.

I add the hot milk, bring to the boil and leave for a few minutes.

I add the grated cheeses, a little salt and pepper.

Once melted, I add the chopped dried mushrooms.

I stir thoroughly until smooth, leave over the heat for a few minutes, then remove and allow to cool slightly.

I add the yolk and mix well.

Leave it to cool in a bowl.

I slice the bread and arrange it on a baking tray lined with baking parchment, spreading a generous amount of cream on each slice.

I finish with some Provolone shavings.
I turn on the grill and let them brown for a few minutes.
Serve hot.