Risotto alla Certosina

Ingredients

• For the freshwater fumét
• 500 g crayfish shells and heads, reserved from the crayfish below
• 200 g perch trimmings and bones, reserved from the perch below
• 1.2 litres cold water
• For the risotto
• 320 g risotto rice, Carnaroli or Vialone Nano
• 400 g live freshwater crayfish (aragostelle), tails shelled, shells reserved for fumét
• 300 g frog legs, cleaned, paired
• 300 g perch fillets, skin removed, pin-boned, trimmings reserved for fumét
• 1 sachet (0.125 g) saffron, steeped in 2 tbsp warm fumét before use
• 80 g unsalted butter, cold, cubed — divided: half for cooking, half for mantecatura
• 1 medium white onion, finely chopped
• 120 ml dry white wine
• 1 tsp fine sea salt, plus more for the blanching water
• To finish
• few drops lemon juice, freshly squeezed, at plating

Method

1. 1
   Combine the crayfish shells and heads with the perch trimmings and bones in a saucepan, cover with 1.2 litres of cold water, and bring to a bare simmer — starting in cold water draws the flavour out of the shells gradually, giving a cleaner, sweeter result than plunging them into boiling liquid. Cook uncovered for 20 minutes, then strain through a fine sieve, pressing the shells firmly to recover every drop of body. Return the fumét to a clean saucepan and keep it at a low simmer throughout the cooking of the risotto; the fumét is ready when it smells clean, sweet, and of the river — not muddy or bitter.
2. 2
   Bring a small saucepan of well-salted water to the boil, add the frog legs, and blanch for 3 minutes, so they firm up enough to hold their shape when folded into the risotto later without dissolving into the rice. Remove with a slotted spoon and drain. They should feel slightly firm to the touch — no longer raw and slippery, but not cooked through — then set aside.
3. 3
   Melt half the butter in a wide, heavy saucepan over medium-low heat, add the onion, and sweat gently until soft and translucent with no colour, so the onion sweetens and softens into the background rather than asserting itself over the delicate river flavours. Add the rice and toast, stirring, until the grains turn lightly opaque at the edges and the pan smells faintly of toasted grain — about 2 minutes — so each grain is sealed and will absorb the fumét evenly rather than turning sodden on the outside while remaining hard at the centre.
4. 4
   Pour in the white wine and stir continuously until it is fully absorbed, so the rice takes on the wine's acidity before the fumét arrives, which balances the final dish rather than leaving a raw, sharp edge. You will know it is ready when the sharp alcohol note has disappeared from the steam rising off the pan.
5. 5
   Begin adding the hot fumét one ladleful at a time, stirring steadily after each addition and allowing each to be absorbed before adding the next, so the friction of spoon against grain coaxes the starch from the rice and builds the creamy, bound consistency the dish depends on. After 10 minutes, stir in the steeped saffron with its liquid, then continue adding fumét and stirring — this is where the dish lives or dies, because the rice must be moved constantly enough to release its starch, yet once the fish and frog legs go in the stirring must become gentler, and a cook who remains aggressive at the finish will shred the perch while one who stops too early will lose the emulsion. Judge the rice by biting a grain: it should offer distinct resistance at the centre with no floury raw taste — about 16–18 minutes total from the first addition of fumét.
6. 6
   When the rice is 3–4 minutes from done, lay the blanched frog legs into the risotto and fold them in gently with a spoon, so their residual heat from blanching means they need only these final minutes to finish cooking without toughening. They require no more than 3–4 minutes in the residual heat of the risotto — the flesh should pull cleanly and easily from the bone when pressed lightly with a fingertip.
7. 7
   One minute before removing the pan from the heat, lay the crayfish tails and perch fillet pieces across the surface of the rice and cover the pan, so the trapped steam cooks them through gently and evenly without the agitation of stirring breaking the fillets apart. Allow approximately 2 minutes; the perch is done when it has turned from translucent to a uniform, opaque white throughout.
8. 8
   Remove the pan from the heat, add the remaining cold cubed butter, and perform the mantecatura — shaking and folding the butter vigorously into the rice — so the cold butter emulsifies with the hot starch into a single, fluid, glossy mass rather than pooling as a separate, greasy layer. No Parmigiano is used here, as its sharpness would overwhelm the freshwater character of the dish; the surface should ripple when the pan is tilted — the Lombard test known as all'onda. Correct for salt.
9. 9
   Spoon into warmed shallow bowls, ensuring each portion receives crayfish, frog legs, and perch in equal measure. Add a few drops of lemon juice directly at table. Serve immediately — risotto waits for no one.