In a pot, heat some olive oil and sauté the onion and garlic. When lightly golden, add the chilies and cook a few minutes until nicely browned. Add the tomatoes and oregano and continue cooking over very low heat for another 20 minutes. Season with salt and pepper.
Mix all the breadcrumb ingredients together well, spread out on a baking sheet and bake at 180ºC for 7 minutes or until the mixture is golden and crisp.
Cook the spaghetti in abundant salted boiling water for 8 minutes or until al dente. Drain well and mix with the sauce.
To serve, sprinkle the spaghetti with the breadcrumbs and garnish with baby basil leaves.