Begin by preheating your oven to 350°F (175°C). While that’s heating up, grab a large mixing bowl. In it, whisk together the beaten eggs and half-and-half. Add the sea salt, black pepper, and Dijon mustard. The mustard adds depth to the flavors that follows.

In a medium skillet, melt the unsalted butter over medium heat. Toss in the diced onions and celery, sautéing them until they soften. This step will release incredible scents. After about 5 minutes, add the minced garlic, thyme, sage, and rosemary. Cook for another minute. The kitchen will smell fantastic.

Once the veggies are fragrant, remove the skillet from the heat and pour the vegetable mixture into the egg mixture. Stir in the white wine vinegar. Then, add the bread cubes into the bowl and mix until everything is just combined. You don’t want to over mix; you still want some texture.

Now, it’s time to fold in the fresh parsley, aged Gouda, Parmesan, and toasted walnuts. Each ingredient adds its own character. The cheeses give it richness, and the nuts add a lovely crunch.

Transfer the mixture to a greased baking dish. Spread it evenly to ensure even cooking. Pop it in the oven and bake for 45 minutes. You'll know it’s ready when the top turns golden brown and a toothpick inserted comes out clean.

Once out of the oven, let the bread pudding stuffing cool slightly before serving. This moment allows flavors to settle, making each bite better.