Prep the Clams: Soak clams in cold water for at least 30 minutes to release any sand. When ready to cook, scrub the shells well and transfer clams to a clean bowl.
Steam the Clams: Add clams to a small pot with white wine and water. Bring to a simmer, cover, and cook until clams just open, about 7–9 minutes.
Remove clams from the pot and reserve the cooking liquid. Let clams cool slightly, then seperate the clam shells and keep them. You'll use them for stuffing.
Scoop out the clam meat, give it a rough chop, and add to a mixing bowl.
Sauté the Aromatics: Preheat oven to 400°F.
Heat a small skillet over medium heat. Melt butter with a drizzle of olive oil, then sauté shallots and bell pepper until just softened, about 3–4 minutes.
Add garlic and thyme and cook for another 30–60 seconds until fragrant.
Make the Stuffing: Add the sautéed aromatics to the chopped fresh clams along with the canned clams, panko, Parmesan, lemon zest, and a handful of chopped parsley.
Mix well, then add 2–3 tablespoons reserved clam liquid, just until the mixture is moist but not wet.
Stuff & Bake: Generously pack the clam mixture into each clam shell and arrange on a baking sheet.
Bake for 18–20 minutes, until the tops are lightly golden.
Finish & Serve: Remove clams from the oven and finish with a drizzle of olive oil, freshly grated Parmesan, and remaining chopped parsley. Serve warm with lemon wedges.