Position a rack in the center of the oven; preheat to 450°.
To make the deviled breadcrumbs, in a medium bowl, whisk the EVOO, mustard, garlic, crushed red pepper and Worcestershire. Add the breadcrumbs and mix until the breadcrumbs are evenly coated.
Arrange the fish on a parchment-lined baking sheet, spacing evenly; season with salt and pepper. Top the fillets with the deviled breadcrumbs. Bake until the crumbs are browned and the fish is opaque in the center, 12 to 15 minutes.
Meanwhile, in a large skillet, heat 1 tbsp. vegetable oil, one turn of the pan, over medium-high.
Add the bacon and cook, stirring occasionally, until browned and crispy, about 8 minutes. Add the leeks and cook, stirring often, until wilted, about 2 minutes. Add the tomatoes and cook, tossing often, until they begin to break down, 2 to 3 minutes more. Season and add the tarragon.
Divide the bacon, leek and tomato mixture among plates; top with the fish. Squeeze the lemon on top.