In a wok over medium-high heat, add oil, garlic, and ginger and cook until aromatic, about 30 seconds. Then add ground pork, break it up, and cook until browned, about 2-3 mins.
Add chili bean sauce, soy sauce, oyster sauce, sugar, ground Sichuan peppercorn, and chili oil to the pork and stir to combine, about 20 seconds.
Add chicken stock then bring to a simmer, continuing to stir, until flavors are incorporated. Lower the heat to medium-low then add the soft tofu and cornstarch slurry and stir gently to incorporate into the sauce ensuring the tofu doesn’t break. Simmer the sauce for 1-2 minutes until thickened.
Once the sauce is thickened and glossy, add chopped scallions, quickly toss again and turn off the heat.
To serve, pour the mapo tofu over white rice then garnish with sesame seeds and more chopped scallions.