Mix together ground beef, ground pork, bread crumbs, beef broth, brown sugar, 1 1/2 teaspoons onion powder, 1 1/4 teaspoons kosher salt, 1 1/4 teaspoons pepper, 1 1/4 teaspoons coriander, 1/2 teaspoon nutmeg, and 1/4 teaspoon allspice in a large bowl until well combined. Shape some of the mixture into 2 or 3 small patties and place remaining sausage mixture in the refrigerator.

Heat oil in a large skillet over medium-low heat. Add sausage patties and cook until browned and cooked through, 3 to 5 minutes per side; do not overcook or sausages will be dry. An instant-read thermometer inserted into the center should read 160 degrees F (70 degrees C).

Taste cooked sausages, adding more salt, pepper, and/or spices to the uncooked mixture as desired. Press uncooked sausage mixture into loaf pans and place in the refrigerator until firm, 2 to 3 hours.

Remove sausage "loaves" from the pans and slice into 1/2-inch slabs. Separate slabs with plastic wrap and store in the refrigerator if you will be cooking all sausage within 4 days. Cook as directed above, over medium-low heat.