In a skillet, melt 2 tablespoons of butter over medium heat. Sauté the red and jalapeño peppers, onion, and garlic until softened; set aside to cool slightly. Beat the cream cheese and sour cream with the spices in a separate bowl. Mix in the cooled sautéed veggies and half of the cheese. Fold in the spinach and artichoke.
Spread the mixture in a baking dish and top with the remaking cheese. Melt the remaining 2 tablespoons of butter. In a food processor, pulse the crouton and melted butter to a fine crumb. Layer it generously over the cheese.
Bake in a preheated 375-degree oven for 25 minutes. Serve the dip warm with crackers or buttery flatbread wedges.