Cook pasta according to package instructions, just until al dente. Don’t overcook! Strain and rinse with cold water. Set aside.
Preheat oven to 350 degrees F. Lightly grease a 8x8 baking dish.
Cook bacon in a large skillet over medium heat until crispy, about 5-7 minutes. Remove bacon to a plate lined with paper towels. Remove some, but not all of the grease from the pan.
Add 1 tablespoons butter to the pan and then whisk in flour. Cook, stirring, for 2 minutes. Reduce heat to low and gradually whisk in milk.
Add the cornstarch to the half and half and whisk until smooth. Gradually add it to skillet followed by mustard, chicken bullion, onion powder, garlic, powder, parsley, salt and pepper.
Cook sauce for a few more minutes, just until it begins to slightly thicken. Remove from heat and stir in shredded cheddar cheese.
Crumble/chop the bacon and add most of it to the pan, reserving a little for topping later. Add cooked pasta and toss to evenly combine.
Pour mixture into 8x8’’ baking dish. Sprinkle parmesan cheese on top.
Add panko, melted butter and olive oil to a skillet (or, I use the pan the pasta was cooked in, just to use less dishes). Cook over medium-high heat, stirring constantly, until crumbs are golden brown.
Evenly sprinkle them over mac cheese. Add remaining bacon crumbles on top.
Bake 15-20 minutes or until bubbly. Serve warm.