In a medium bowl, gently mix the ground beef with sea salt, black pepper, and garlic powder.
Heat the avocado oil in a skillet over medium-high heat until shimmering.
Form the beef into a large patty or crumble it into the pan, cooking for 4-5 minutes per side until browned and cooked through.
While the beef cooks, prepare the base by placing the mixed baby greens in a large bowl.
Slice the cherry tomatoes, red onion, and avocado.
Arrange the cooked beef on top of the greens, then add the tomatoes, onion, avocado, and dill pickles.
Drizzle with yellow mustard and serve immediately while the beef is warm.