Smaller, delicate shrimp with sweeter flesh such as spot prawns (currently in season!) are best for this recipe. The size and bouncier texture of larger shrimp like black tiger would overpower the simple flavours of the pasta.
I got live B.C. spot prawns from T&T at $40 per pound (suffice to say this is a splurge meal). When buying live shrimp, have a cooler with ice ready to store them on the ride home (don’t leave them kicking around for more than a few hours). Do not put them in tap water: The chlorine kills the prawns and deteriorates the flesh. Prepare the prawns by quickly twisting off their heads, and save them, along with the shells for stock. Place the peeled and cleaned shrimp in a bowl, cover with ice and refrigerate for up to three days, pouring out any water in the bowl each day and replacing any melted ice. For smaller shrimp like spot prawns, 30 minutes of marinating in lime juice is the ideal time. Leave it in there for too long and the flesh will become chalky in taste.
Beck calls for veal or fish stock, but I used the shrimp shells and heads to make just enough stock for the dish. If chervil isn’t available, substitute with parsley. As for the pasta, Beck prefers the De Cecco brand, specifically the “no. 12” spaghetti, for the home cook.
Heinz Beck’s Cacio E Pepe
Clean, peel and devein shrimp, reserving heads and shells. Refrigerate peeled shrimp in a bowl filled with ice until 30 minutes before serving.
In a small saucepan, add shrimp shells and heads along with garlic. Add enough cold water to just cover shells. Season with salt and pepper. Bring to a boil and turn heat down to a gentle simmer for 45 minutes, or until stock has reduced to about 2/3 cup. Strain through a fine mesh sieve and transfer stock to a large saucepan.
In a small bowl, whisk together lime zest and juice along with olive oil and a pinch of salt. Toss in peeled shrimp and let marinate in fridge for about 30 minutes.
Meanwhile, fill a large pot with water and season with salt. Bring water to a boil over high heat. Cook pasta until it is still slightly underdone, about two minutes away from being al dente.
Bring large saucepan of stock to a simmer over medium heat. Add pasta to pan, reserving pasta water. Finish cooking pasta in pan, tossing frequently with tongs. If stock dries out, add a bit of reserved pasta water to finish cooking pasta. When pasta is al dente, remove pan from heat and let rest for 30 seconds.
Combine pecorino and 1 tsp (5 mL) black pepper in a medium-sized bowl and slowly add to pan, tossing frequently with tongs to allow residual heat of pasta to melt cheese. Toss until pasta is creamy. Taste and season with additional black pepper if necessary.
Divide pasta evenly into four plates. Garnish with more pecorino and herbs. Top with strained, marinated shrimp.