Bring a large pot of salted water to a boil. When the water is boiling, cook the pasta according to box directions.
Heat a large sauté pan with sides to medium high heat. Add just enough olive oil to lightly coat the bottom. When the pan is hot, add the pancetta and cook for about 2 minutes, until crispy. Using a slotted spoon, transfer the pancetta to a bowl and set aside.
There should be at least 1 tbsp of fat left in the pan from the pancetta; if not, add1 tbsp of olive oil. Increase the heat to medium high, then add shrimp to pan along with a generous pinch of salt and black pepper. Sauté the shrimp for about 2 minutes, until seared on both sides. Remove shrimp from pan and place in the bowl with the pancetta.
Reduce the heat to medium, then add the shallots and sauté for 2 minutes, until beginning to soften, lowering heat if pan becomes too hot. Add garlic and cook for 3 more minutes, stirring constantly, being careful not to let the garlic brown.
Add wine and BOU cube to the pan and whisk until the cube has dissolved. Once the liquid comes to a boil, let it reduce for about 1-2 minutes, until it has almost fully evaporated.
Add the peas, coconut milk and red pepper flakes to the pan and give it a good stir. Bring it a boil then reduce heat to medium. Allow the liquid to thicken a bit, stirring occasionally, for about 2-3 minutes.
By now your pasta should be cooked and drained. Using tongs, add the pasta directly to the pan. Add the shrimp and pancetta along with any juices from the bowl, then the tarragon and lemon zest. Toss well to combine then simmer on low heat for about 3-5 minutes, stirring occasionally, until shrimp has cooked through.