Cut the onion and garlic cloves into fine cubes. In a large saucepan over medium-high heat, cook the round beef with the onion and garlic, breaking it apart as it cooks, until cooked through with no pink remaining, about 8-10 minutes.
Add the sieved tomatoes, chopped tomatoes, and kidney beans to the saucepan.
Cut the celery into pieces and add to the pot.
Squeeze the lime and add the juice to the pot.
Reduce heat to medium and simmer for 15 minutes.
Pour the chilli into a bowl and garnish with sliced avocado.