Make the breadcrumb topping. Place 2 Tbsp butter and 2 Tbsp pesto in a small skillet over medium heat. Once melted, stir in ½ cup panko breadcrumbs. Cook, stirring often, until they turn a deep golden brown, about 2-3 minutes. Transfer to a small bowl, season with a pinch of flaky sea salt, then set aside.
Infuse oil. In a large skillet with deep sides, heat ¼ cup of extra virgin olive oil over medium heat. Add 4 smashed garlic cloves and the halved fresno chili then cook until fragrant and the garlic has lightly browned, about 2-3 minutes. Remove the garlic and chili, discard, then add 2 anchovies. Use a spatula to help them break down and dissolve into the oil.
Cook tomatoes. Add two pints of halved cherry tomatoes then cook, stirring occasionally, until reduced and jammy, about 8-10 minutes. Season lightly with kosher salt and black pepper.
Cook pasta. Bring a large pot of water to a rapid boil, then season generously with a couple tablespoons of kosher salt. Add linguine then cook until about 2 minutes shy of al dente. Reserve at least 1 cup of pasta water before draining.
Finish in sauce. Add ½ cup of the reserved water to the tomatoes, then add cooked pasta, the small lump crab meat, 2 tsp lemon zest, juice from 1 lemon, 2 tsp sherry vinegar, and the fresh basil and tarragon. Stir really well.
Add crab. We’re adding the larger jumbo lump crab towards the end so that the pieces remain intact – add that now, along with more of the reserved pasta water if you want to create more of a sauce. Taste and adjust seasoning.
Serve. Divide between bowls, then drizzle each with a little extra virgin olive oil. Sprinkle as much of the pesto breadcrumbs on top as you like, then finish with a pinch of flaky sea salt, extra black pepper, and thinly sliced chives. Enjoy!