Gently mix tofu with flour and cornstarch to coat evenly.
Heat oil in a large non-stick or cast iron skillet. Add tofu and cook for a few minutes to form a crust on each side turning frequently. Take out the cooked tofu and set it aside.
In the same skillet heat sesame oil over medium heat. Add garlic, ginger and chili flakes and cook for about one minute or until fragrant.
Then add sliced shallots and fry until translucent for about 1-2 min.
Now add ketchup, soy sauce, vinegar, and honey. Cook the mixture for 2-3 minutes.
Add broth and bring mixture to boil.
Add cornstarch mixed with water to thicken the sauce and cook the sauce further for 3-4 min.
Finally, add tofu and gently mix to combine.
Garnish with green onions, sesame seeds (optional) and serve warm.