In a large saucepan of boiling salted water, cook orzo until al dente, following package instructions. Drain and set aside.
Melt butter for cheese sauce in a medium-large pot over medium heat. Sauté shallot until translucent and then add garlic and sauté until fragrant, about 1 minute. Whisk in flour and cook while whisking for another minute. Gradually pour in half and half cream, followed by milk, whisking constantly. Continue to whisk until sauce thickens, about 10 to 12 minutes. Add mustard, cayenne pepper, nutmeg and salt. Gradually whisk in cheese until completely melted. Season with salt to taste, remembering that the cheese adds some saltiness to it already. Remove from heat, reserve 1/3 of cheese sauce and set aside. Whisk in eggs. Then gradually stir in pasta and set aside.
Preheat oven to 425°F (220°C). Spray or grease nonstick mini muffin tins and dust each cup with Parmesan cheese and panko and set aside.
In a large skillet melt butter for breadcrumbs over medium heat. Stir in breadcrumbs and toast them in the pan, stirring constantly until golden brown, about 5 to 10 minutes. Re-move from heat and season with salt and pepper to taste and set aside.
Divide mac and cheese evenly into mini muffin tins, pressing down on each one gently. Sprinkle each with Parmesan cheese followed by bread crumbs and bake until golden brown and heated through, about 10-12 minutes. Remove from oven and place on a baking rack. Let sit in muffin tin until they can maintain their shape and are set, about 10 minutes. Using a small spoon, carefully loosen the mini mac and cheese bites, and transfer to a platter.
While the mini mac and cheese bites are baking, begin making the fonduta. In a medium skillet, heat oil on medium and add both fresh and sun-dried tomatoes and chili flakes. Cook, stirring often, for 10 to 12 minutes until fresh tomatoes have completely broken down and most of the moisture has evaporated. Season with salt to taste and remove from heat. In a food processor, purée the mixture along with reserved cheese sauce until smooth. Serve alongside mini mac and cheese bites and sprinkle them with chopped basil.