Hi, Danny.
On a Fast Day, you want your breakfast to be high in protein [ex: 15 g.], low in carbs [such as carbs from fruit], as low in added sugar as possible. Eggs are a good way to go. In our house, we always have eggs on Fast Days: baked eggs on Monday, omelettes on Thursday.

Here is a recipe which we like. It might fit into your ‘grab-and-go’ lifestyle: if you fold the toast in half, then you have an egg sandwich.
Egg-Mushroom Toast 268 calories 6.6 g fat 4.2 g fiber 16 g protein 43 g carbs 243.3 mg Calcium PB GF – if using GF bread This is yummy. The eggs are creamy and the mushrooms lend a mysterious layer of flavor. I like this better than poached eggs.
1 piece 70-cal multi-grain bread one 2-oz egg 1/2 oz mushrooms, chopped 1 Tbsp chives, chopped 1 tsp thyme 1 oz of apple blackish coffee, blackish tea, or lemon in hot water 5-6 oz smoothie or natural apple cider
Toast the bread. Spritz the non-stick saute pan with oil or spray and gently cook the mushrooms. Put the chives, thyme, salt, and pepper in with the egg and beat it up. Scramble lightly with the mushrooms, keeping the eggs moist. Turn out over the toast and plate the fruit.

@Dream. Took me longer to read some of the recipes than it takes me to have breakfast! Everyone has a different take on what healthy is. Are you overweight and wanting to lose weight? Or are you the correct weight and fit? If fit you could still incorporate a lot of whole fruit (never fruit juice). Just avoid processed grain based products and processed foods in general. No bread, muffins, bagels, cakes, biscuits etc. No breakfast cereals (pure junk). No juice. Not a big fan of smoothies as they destroy your sense of portion size.

I just have two scoops of plain greek yogurt with mixed berries, almonds and pumpkin seeds.

Here’s are some more recipes:

Citrus Breakfast: 290 calories 1.6 g fat 3.6 g fiber 21 g protein 48 g carbs 938 g Complex] 289 mg Calcium] PB GF Delicious, nutritious, and filling, this is a great breakfast for anyone, anyday. And it has tons of Vitamin C and A and D.
½ cup reduced-fat cottage cheese 2 Tbsp fat-free French Vanilla 1 clementine, peeled and sectioned 2 Tbsp black currants 5-6 oz fruit smoothie or green smoothie or natural apple cider blackish coffee, blackish tea, or lemon in hot water
Combine all the dairy and fruit [or combine the dairy and garnish with fruit after plateing]. Knowing that I would have a busy morning, I did this the night before and refrigerated it. Great for a grab-and-go meal. With the hot beverage and smoothie, it is a vitamin-blast.

Roman Breakfast: 270 calories 3.5 g fat 4.2 g fiber 14.2 g protein 41 g carbs [– g Complex Carbs] 187 mg Calcium PB Though a bit unusual, this is a very good plate of breakfast food, based on foods available to Romans in the 1st century BCE. It is satisfying and flavorful. Try it.
1 Pan Muffin [see ..Not by Bread.. Feb-7-’18] 1 oz pear 1 oz cooked chicken 1 oz radish 1 oz cucumber [optional: ½ medjool date = ¼ oz] blackish coffee or blackish tea or lemon in hot water 5-6 oz green smoothie or fruit smoothie or unpasturized apple cider
Dice all the fruits and vegetables. Add a good finishing salt and gently stir to combine. HINT: I did this the night before and refrigerated the mixture. Prepare the pan muffin or take from freezer with time to thaw/heat. In the time it takes to brew the coffee, you can plate the muffin and the fruit-veg mixture. Romans did not drink smoothies or coffee, but we will. NOT GOOD FOR FODMAP

I’ve recently ventured into a Paleo diet and it did wonders, so my usual 3 eggs and oats have been replaced by Paleo recipes. One day it’s frittata, the next day it’s salad.

If you’re still needing tips on healthy breakfast, there are some more in this article:
https://understandingpaleo.com/paleo-breakfast-ideas/