Heat a wok over medium-high heat. Add oil and then shallots and mushrooms. Saute until golden brown and very tender, 3 to 4 minutes. Season with some salt.
Add broccoli and bell peppers and saute for 1 minute more.
Whisk cornstarch into water.
Pour stir-fry sauce and corn starch / water mixture over mushrooms and stir to combine. Simmer until sauce thickens, ~2 minutes.
Add noodles and stir to coat noodles in sauce.
Divide stir-fry between bowls. Serve with lime wedges on the side and some extra red pepper flakes or hot sauce if you’d like. Enjoy!