Thinly slice 1 small carrot and 1/2 small red onion and 1/2 red bell pepper. Heat 1 tbsp oil in a small pan over medium heat, add 1/2 tsp mustard seeds and cook until they pop (about 30 sec). Add sliced vegetables, 1/4 cup white vinegar, 1 tbsp sugar, 1/4 tsp salt, and 1/4 tsp crushed red pepper. Cook 1–2 minutes to slightly soften, remove from heat and let cool. Finely chop before using; measure 1/2 cup for the dip.

Make the Fish Dip

Flake the drained canned fish into a medium bowl, removing any remaining bones or skin. Gently mash with a fork until mostly broken down but still possessing some texture.

In a separate bowl, beat together softened cream cheese, mayonnaise, and sour cream until smooth and creamy. A whisk or electric hand mixer on low works well.

Mix in fresh lemon juice, lemon zest, Worcestershire sauce, Old Bay, black pepper, and kosher salt until evenly incorporated.

Fold the flaked fish into the creamy base until evenly distributed. Taste and adjust seasoning: add up to 1/2 tsp more Old Bay or extra lemon juice if desired.

Add Pickled Ingredients & Finish

Fold chopped pickled jalapeños and the finely chopped escovitch vegetables into the fish dip, reserving about 1 tablespoon of each for garnish. If the escovitch pickle liquid is bright and acidic and you want more tang, stir in up to 1 tsp now (taste as you go).

Transfer the dip to a serving bowl. Sprinkle the top with the reserved escovitch and jalapeño pieces, a dusting of extra Old Bay (about 1/4 tsp), and the chopped fresh parsley. Garnish with lemon wedges on the side.

Cover and chill for at least 30 minutes to let flavors meld (recommended), or serve immediately if short on time. Chilling will firm the texture slightly.

Serve

Bring chilled dip to the table with assorted crudités and crackers. Encourage guests to squeeze lemon over portions to brighten flavors. Leftovers keep covered in the refrigerator for up to 3 days.