How to Make It
Pour 1 of the beers into a small saucepan. Bring to a boil over medium-high. Reduce heat to low, and simmer, stirring occasionally, until reduced to about 1/8 cup, about 45 minutes. Remove from heat, and cool to room temperature, about 10 minutes. Transfer reduced beer to a medium bowl. Add sour cream, whole-grain mustard, Dijon mustard, honey, lemon juice, chives, pepper, and 1/4 teaspoon of the salt; whisk to combine. Set aside.
Bring water to a boil in a large stockpot over high. Add lobsters, and cook 6 minutes. Transfer lobsters to a bowl of ice and water. Using scissors or a chef’s knife, remove the tail and claws. Remove the meat, and cut meat into 1-inch pieces. Discard shell.
Stir together flour, cornstarch, 1/2 teaspoon of the salt, and remaining 1 beer in a medium bowl. Place panko in a separate bowl. Dip lobster pieces in flour mixture, shaking off any excess, and roll in panko.
Pour oil to a depth of 3 inches into a heavy-bottomed stockpot or Dutch oven; heat to 325°F. Working in batches, add coated lobster pieces, and cook until golden brown, about 3 minutes. Transfer to a plate lined with paper towels to drain, and sprinkle fried lobster evenly with remaining 1/4 teaspoon salt. Serve hot with lager-mustard sauce.