This dish is an homage to the amazing shrimp on the Pacific coast of Mexico and more specifically, Mazatlán. Every morning around 6:30, the shrimp boats come in and beautiful shrimp arrive at the markets. Pairing the sweet shrimp with the fruity but tart tomatillo balances the dish with the nuttiness of the toasted pasta and the heat of the serrano.
Heat a large skillet over high heat for 2 minutes and toast the fideo, tossing constantly, until most of the fideo has browned, 3 to 4 minutes; transfer to a medium bowl and set aside until ready to use.
Heat the bacon fat in the same skillet over high heat and cook half the shrimp until just beginning to brown, about 1 minute per side; transfer to a plate. Repeat with the remaining shrimp.
Reduce the heat to medium high and add the onion, poblano, garlic, serrano, tomatillos and salt in the same skillet; cook, tossing occasionally, until tender and just beginning to brown, 6 to 8 minutes. Add the stock and fideo and bring to a boil; cover, reduce the heat to low and cook until all of the liquid has been absorbed, 17 to 22 minutes. Remove from the heat and let sit for 5 minutes. Arrange the shrimp on top, cover and let sit for 5 minutes to heat the shrimp through.
Serve the fideo topped with avocado slices and cilantro leaves.
If you have time, use your shrimp shells and tails to make a stock: saute in 1 tablespoon of oil in a medium saucepan until red, add 3 cups water and simmer for 30 minutes; strain and use for the fideo.