Combine miso, butter, and tamari in a small bowl and mask together with fork to combine.
Prepare noodles according to package directions.
Drain noodles, reserving 1/2 cup cooking liquid.
Add reserved cooking liquid to miso mixture and stir to combine.
Heat canola oil in large skillet on medium high heat.
Add shallots to pan and stir fry for 1-2 minutes.
Add shitakes and stir fry for another minute.
Add bok choy and haricort verts and cook for 2 more minutes.
Add miso mixture and noodles and toss to combine.
Garnish with scallions and serve immediately.