In a food processor, blend the tuna, egg yolk, lemon juice, salt, and black pepper until combined.
Slowly drizzle in olive oil until emulsified into a smooth paste. Season to taste. This is the Tonnato sauce.
Cook pasta until al dente.
Toss the pasta in the Tonnato sauce with 2-4 tbsp of pasta water
Garnish with more tuna, parsley, and lemon zest.
