For the Ranch Slaw:
1/2 cup sour cream
1/4 cup buttermilk
2 tablespoons super-fine sugar
3 tablespoons grated onion
Juice of 1/2 lemon
2 tablespoons white vinegar
1 teaspoon celery salt
1 teaspoon black pepper
2 tablespoons each finely chopped dill, chives and parsley
1/2 pound white cabbage, thinly shredded
For the Barbecue Sauce:
2 tablespoons butter
1/2 onion, finely chopped
2 large cloves garlic, finely chopped or grated
2 tablespoons tomato paste
2 tablespoons puréed chipotle in adobo
1 cup beef stock
1 tablespoon Worcestershire
1 tablespoon Tamari/soy sauce
2 scant tablespoons light brown sugar
For the Burgers:
1 1/2 pounds 80% lean ground sirloin
Kosher salt and coarse black pepper
Vegetable or olive oil, for drizzling
4 soft burger rolls with sesame seeds
Sliced bread-and-butter or dill pickle chips
1/2 small white onion, finely chopped
For the slaw, whisk up dressing in a large bowl, add cabbage and toss to coat. Chill until ready to serve.
For the sauce, heat a skillet over medium heat, melt butter and add onions, garlic, salt and pepper. Soften 6-7 minutes then add chipotle purée and tomato paste. Stir a minute and add stock, Worcestershire, Tamari and sugar. Bring to a bubble then reduce to low simmer.
Heat a cast-iron griddle or skillet over medium to medium-high heat.
Make 4 patties that thinner at the centers than edges for even cooking. Season patties liberally with salt and pepper.
Add a drizzle of oil to the griddle or skillet, and cook patties about 8 minutes, turning occasionally.
Arrange bun bottoms on a platter or plates and top with pickles and onions.
Turn burger patties in the barbecue sauce to coat then place on buns, top with slaw and set bun tops in place.