In a large pot, add olive oil and bacon, then place over medium heat. Cook bacon until crispy, then transfer to a paper-towel-lined plate.
Add onion, celery, carrot, ½ teaspoon salt, and ¼ teaspoon black pepper to pot and cook until soft, about 5 minutes. Then add garlic and cook until fragrant, about 1 minute more.
Add ground beef and 1 teaspoon salt and cook, breaking up meat with a wooden spoon, until no longer pink, about 6-7 minutes. Drain.
Stir in mustard, broth, and diced tomatoes. Bring to a simmer over medium heat, and let cook for about 10 minutes.
Turn heat to low and stir in cheese, half and half, and flour. Cook until the cheese has melted and soup is thickened, about 12-15 minutes.
Top with crumbled bacon, more cheese, dill pickles, and toasted sesame seeds.