Burgers: In a large bowl, whisk soy sauce with rice vinegar, sugar, garlic and ginger until combined. Stir in onion, breadcrumbs and egg. Crumble in beef; gently mix until well combined. Divide mixture into 6 equal portions; form into 3/4-inch (2 cm) thick patties. Make a thumbprint depression in centre of each patty (to prevent rounding while grilling). Refrigerate, covered, for 30 minutes (or up to 1 day.)

Cucumber Salad: Meanwhile, in a large bowl, whisk vinegar with soy sauce, sugar and chili paste. Add cucumbers; toss and set aside until ready to serve.

Sautéed Vegetables: Whisk soy sauce with sugar, garlic and ginger. Heat sesame oil in a large, nonstick skillet set over medium-high heat. Add mushrooms; cook for 5 minutes, stirring occasionally, or until softened and lightly browned. Add carrots; cook 2 minutes or until softened. Add spinach and soy sauce mixture. Cook, stirring constantly, for 2 minutes or until wilted. Remove from heat, cover and keep warm.

Preheat grill to medium heat; grease grates well. Grill patties for 5 to 7 minutes per side, testing doneness with a digital instant read thermometer inserted sideways into centre of each patty to ensure patties are cooked to 160°F (71°C).

Garnishes: Assemble burgers in rolls over 6 serving plates; top each burger patty evenly with sautéed vegetables, a fried egg and sesame seeds. Serve with cucumber salad on the side.

Korean-style Mayo: Combine 1/4 cup light mayonnaise and 1 tbsp Korean chili paste (Gochujang). Note: use 2 tbsp chili paste for those who like it spicy.

Notes

• For a gluten-free option, use Tamari instead of soy sauce and serve in a lettuce leaf instead of a roll or bun.

• Transform this into a Burger Bowl by omitting the roll or bun and serving recipe over cooked whole-grain rice.

• To Cook Indoors: Cook burgers in a cast-iron skillet over medium heat.