Wash and peel the potatoes. Cut them into 1/4th inch thick pieces and place in a cold bowl of water for about 30 minutes. (If you plan on soaking longer than 30 minutes, place in the fridge covered)
Adjust the oven rack to be the 2nd from the top. Preheat the oven to 425 degrees F. Line a large pan with parchment paper (do not skip the parchment) and set aside.
Remove the fries from the water and dry VERY thoroughly.
Toss together seasoned salt (1/2 tablespoon), pepper (pinch), chili powder, garlic powder, and cumin. Remove 1 teaspoon of these spices.
Place the COMPLETELY dried fries on the prepared sheet pan. Cover with 1 to 2 tablespoons olive oil and the 1 teaspoon of spices. Toss and then quickly separate to be in one layer.
Bake in preheated oven for 15 minutes, remove, flip, and bake for another 15 minutes.
MEANWHILE, prepare the fish. Take the Panko, dried thyme, minced garlic, and 2 tablespoons olive oil and place in a large pan over medium to medium high heat. Stir pretty constantly for 4-6 minutes or until the Panko is toasted. Remove from the heat and set aside.
Grab 2 other bowls. Put flour in one bowl. Place the egg and Dijon mustard in the last bowl. Briskly whisk the egg and mustard until well combined.
Cut the 10 ounces of cod into 6 equal sized pieces. Generously salt (about 1 teaspoon) and pepper (about 1/2 teaspoon) both sides of each of the cod pieces.
Being gentle, dredge each piece in flour. Be generous you should use up most of the flour.
Then dredge each piece is the mustard + egg mixture.
Finally dredge each piece in the panko. All 3 of the mixtures should be all used up.
Remove the fries from the oven and separate them to either side of the pan so there is a section in the center.
Place the 6 pieces of fish in the center and put back in the oven for 9-13 minutes or until the fish is cooked through and the fries are crispy. Broil for 30 seconds if desired.
Remove from the oven and toss the fries with another teaspoon (or to taste) of the fry seasoning mix. Toss with the Parmesan cheese if desired.
Enjoy immediately with tartar sauce and fresh lemon.