In what may be surprising to many, they recommend that about half the breakfast (between 44 per cent and 55 per cent to be precise) should be made up of carbohydrates - while avoiding sugary or processed foods, such as white bread.
They then suggest the breakfast should be made up of about 10-15g of fat, 25g of fibre, and 13 to 20g of protein; they point to studies which suggest a high-protein diet may lead to weight loss.
They also advise not to have any more than 6g of added sugars in your morning meal.
The idea is to have a filling breakfast that's high in protein, nutrient-rich and low in added sugars, which gives you the perfect balance of almost every food group.
But if that sounds too complicated to work out every day, then don't panic.
The pair have come up with three examples to show you what the ideal breakfast for weight loss looks like.
The first is 'steel-cut oats with fruit and nuts' - aka porridge made with protein-rich coarse oatmeal.
The nutritionists advise to make a 118g bowl of porridge made half with water, and half with unsweetened soya milk.
They suggest topping with blueberries, chopped walnuts and a drizzle of maple syrup.
If that doesn't entice you, then Stephanie and Willow also suggest a breakfast of natural peanut butter on wholemeal toast, using two tablespoons of the spread and topping with a banana and a sprinkle of cinnamon.
Another alternative best breakfast is scrambled egg made with two eggs, spinach, and a tablespoon of chopped onion on wholegrain toast.
They recommend serving it with fresh fruit, such as raspberries or blueberries.
Three of the best breakfasts to eat for weight loss
• Porridge made with coarse oatmeal, using half water, half soya milk, topped with blueberries and walnuts
• Natural peanut butter on wholemeal toast, topped with banana and cinnamon
• Scrambled egg with spinach and onion on wholegrain toast