Preheat the oven to 350°F. Lightly grease a 9 by 13-inch baking pan. Bring a large pot of salted water to a boil.

Cook the macaroni in the boiling salted water according to the package instructions, until soft. Drain the pasta and set aside.

Melt the vegan butter in a large pot over medium heat. Add the green onions and garlic and sauté until softened, about 2 minutes. Add the flour and cook until flour is slightly toasted with a slightly nutty aroma, stirring with a whisk, about 3 minutes.

While whisking, pour in 4 cups of the pea milk and continue to stir until the sauce is thickened and smooth, about 5 minutes. Make sure to run the whisk along the edges of the pot to get all of the flour.

Turn the heat down to low and add the salt, vegan chopped cheddar, and vegan cheddar shreds. Cook for about 5 minutes, stirring occasionally, until most of the shredded cheese is melted. If the sauce is lumpy, add an additional ½ cup of pea milk and whisk until smooth.

Add the cooked macaroni and stir well to coat.

Pour the mixture into the greased baking pan. Cover with foil and bake for 20 minutes, or until the sauce is bubbly.

Let it cool for a few minutes and serve hot.