Prepare the crust. Toast panko breadcrumbs and walnuts in a dry skillet over medium heat for approximately 5 minutes; tossing often. They will become lightly toasted and fragrant. Transfer to a mixing bowl. Add butter and salt then mix until will incorporated.
Lay a large piece of parchment paper out on the counter and top with crust mixture. Cover with another large piece of parchment paper. Press down to flatten slightly then with a rolling pin; roll out to 1/4 inch thick. Place in freezer on a flat surface to set.
Meanwhile prepare the arugula pesto. Toasts walnuts in a dry skillet over medium heat for approximately 5 minutes; tossing often. They will become lightly toasted and fragrant
In a food processor, combine arugula, Parmesan cheese, walnuts, garlic and kosher salt. Turn on and slowly add in extra virgin olive oil and walnut oil until a paste forms, approximately 30 seconds. Transfer to a bowl, cover with plastic wrap and place in refrigerator.
Now prepare the halibut. Preheat broiler on high.
Remove crust from the freezer. Keep the parchment paper on and using kitchen shears cut 6 pieces into the same size as the halibut filets.
Working in 2 separate saute pans, evenly heat canola oil over medium high heat. Season halibut filets with kosher salt. Once the oil is hot and smoking; add 3 halibut filets per pan and sear for 5 minutes on one side then flip and sear for 3 minutes longer on the other side. Working in 2 pans will allow the filets to cook evenly and not be over crowded in the pan.
Remove one side of parchment paper from the crust and top each piece of halibut. Peel away the second side of parchment repeating until all 6 are topped.
Transfer the saute pans under the broiler for approximately 2 minutes or until crust is golden brown and toasted.
Spoon arugula pesto on the bottom of a large serving platter. Place crusted halibut on top and serve family style.