Blue potato tortelli with mushrooms and ricotta, in butter and sage

Delicious, soft ravioli with lovely blue potatoes, which can be replaced by ordinary potatoes. Versatile too: replace the mushrooms with the same weight of boiled spinach, artichokes or your preferred vegetable.
INGREDIENTS FOR 2 PEOPLE
TORTELLI
500 g blue potatoes (from the Giudicarie)
150 g '00' flour
Half an egg
Salt
FILLING
100 g ricotta
150 g sautéed mushrooms
4 tablespoons grated Parmigiano
Salt, pepper
SAUCE
100 g butter
Extra virgin olive oil
4/5 sage leaves
Grated Parmigiano
I put the potatoes in cold water and bring to the boil. They take about 35/40 minutes; pierce to check.

While they cook, I prepare the filling, chopping mushrooms previously cooked with oil, parsley and garlic.

I put them in a bowl and add ricotta.

Parmigiano and a pinch of salt if needed. The filling should be fairly firm.

I mix and set aside.

I peel the potatoes while hot.

I rice them onto the board.

I make a well and add half an egg, lightly beaten with a fork.

I add more than half the flour and a little salt.

I knead by hand, adding the remaining flour if needed. The dough should be neither sticky nor too hard. I form an even ball without overworking.

I generously flour the board and roll to about half a cm thick.

I cut discs with an 8 cm food ring.

I put a small ball of filling in the centre.

I place on a floured ravioli mould and close; without one, seal with a fork.

I press lightly to form a plump raviolo.

I prepare them all on a floured, parchment-lined tray.
I made 21. With a second course, this quantity serves 4; as a complete meal for 2, there will not be many left.

I gently add all the ravioli to boiling salted water. After they float, I cook for 2 minutes.

I melt the butter, a little extra virgin olive oil and sage in a large frying pan without frying them.

When they start sizzling, I add a small ladle of cooking water and move the pan to emulsify into a thick cream. This makes it easier to digest than traditional browned butter.

I drain the ravioli into the sauce, coat well and sprinkle with Parmigiano.

I serve drizzled with the sauce.