Depending on where you’re from you may be picturing entirely the wrong things for biscuits and gravy. The biscuits are soft, flaky, buttery pastries and the gravy is a white sausage gravy made from flour, milk, and ground sausage. If you look up “biscuits and gravy” the pictures will show you what it looks like. It’s a common breakfast from the US south, although it exists in all parts of the US.
It's a staple southern American Southern US breakfast dish. Drop biscuits (similar to buttermilk biscuits, but it'd denser and fluffier. No layers either), covered with sausage gravy. If you're not from the US/North America I'm not sure if there's an equivalent to breakfast sausage. I hope so! Because if you have the time to make some I would really recommend it!
Couple of tips for anyone looking to make some biscuits and gravy:
Use shortening in your biscuits, idk what it does different but it works best imo.
If you're going to use biscuit mix, use Formula L if you can find it. It's the best. Good for pancakes too!
Let your roux get a some color before adding the milk. Pale sausage gravy doesn't taste nearly as good. Just use low heat and keep the sausage and flour mixture moving to ensure you don't burn it.
Use full fat milk for better flavor.
After you add the milk and it warms back up, throw 4 or 5 chopped up fresh sage leaves into your gravy. Sage, fennel, and pepper are a big part of the flavor profile of American breakfast sausage, adding a little extra really helps the flavor pop!
And finally, let the gravy get thick! Watery gravy should be illegal
For vegetarians: beyond sausage works great if you want to try it! It browns quicker than regular sausage though, so keep an eye on it. And you might need to add a little extra fat, butter or margarine works well.
This is all great advice, but I would add to it that biscuits and gravy is terrible if there is no black pepper in it. It's definitely a required ingredient. Sage and others are optional, but pepper is a must.
And don't skimp on the sausage. The number one mistake that restaurants make is skimping on the sausage. It shouldn't taste like milk.
The number two mistake that restaurants make is trying to make it fancy and adding too much random stuff to it. You don't need to add bacon and green onions and cheese and on and on. It's not grits. It's delicious on its own as a nice, simple recipe.
Non-southerners beware, flour that grows well at higher latitudes is "harder", i.e. has more gluten, while wheat from the south is "softer" / less gluten. You may need a softer flour to make really great southern-style biscuits, and that can be tough to come by outside the south.