To make the mashy peas: Bring 6 cups of water to a boil in a medium sauce pot and add 1 tablespoon kosher salt to the water. Have a bowl with half ice cubes and half water ready to shock the peas. Add the peas to the boiling water and cook until tender, approximately 4 minutes. Remove from boiling water and place peas in the ice water to stop the cooking. Drain the peas. Place peas in a food processor and pulse a couple of times, then add in the chopped garlic and pulse to combine. Continue to pulse the mixture and drizzle in the olive oil. Add in the tarragon, parsley, chives, basil, mint, lemon juice, 1/2 teaspoon kosher salt and 1/4 teaspoon black pepper. Lightly pulse until incorporated. Remove from processor and keep chilled.
For the Salmon: Heat a large non stick saute pan over medium- high heat. Lightly season the salmon portions with the 1/2 teaspoon kosher salt on both sides. Add the 2 tablespoons vegetable oil to the pan. Carefully place the salmon portions into the pan, skin side up. Reduce heat to medium. Allow salmon to cook to a golden brown. After about 4 minutes, flip the salmon and allow to finish cooking, about 5 more minutes. Remove from pan.
For the pea shoot salad: Toss all ingredients for the salad in a mixing bowl, set aside.
To assemble: Heat a non stick pan to medium-high heat, place the cut sides of the lemon down in the pan to sear until golden brown.Divide the mashy peas between two plates, place a portion of salmon over the peas, top with the pea shoot salad. Serve with the seared half lemon on the side.