Cut the broccoli: Use a sharpened knife to separate the broccoli head from the main stem. Cut the head into smaller florets, then rinse them under running water. Drain the florets in a salad spinner.

Cut the potatoes: Clean the potatoes under the running faucet. Use a vegetable brush or your hands to gently scrub off the dirt on the outer skin. Peel off the skin using a peeler. Chop the potatoes into smaller cubes to the desired size.

Cut the onion: Slice off the two ends of the onion. Peel away the outer skin. Remove the core and start cutting it into smaller chunks.

Chop the scallions: Place the scallions on a cutting board. Use a sharp knife to remove the top part and the root end, then cut them into smaller chunks, about 1/4 to 1/2-inch.

Mince the garlic: Separate the garlic cloves from the bulb and trim off the tips. Peel away the skin. Mince the cloves well.

Slice the French baguette: Use a serrated knife to cut the baguette into 1-inch slices

Reheat the baguette: Line your air fryer with parchment paper (optional). Arrange the baguette slices separately into the frying basket and air-fry at 350°F for 4 minutes. Remove and set them aside.

Sauté the onion: Place a large cooking pot over medium heat. Add 1 tbsp olive oil, 1/2 tbsp minced garlic, and 2 oz onions. Stir-fry until fragrant, about 2 minutes.

Cook the broccoli: In the same pot, add 8 oz broccoli and 4 oz potatoes. Cook for another 3 minutes.

Combine other ingredients: Pour in 1 1/2 cups unsalted chicken broth, 1/2 cup whole milk, 1 tbsp heavy cream, 0.25 oz shredded parmesan cheese, 0.25 oz grated cheddar cheese, 1/4 tsp salt, and 1/4 tsp pepper. Bring the mixture to a boil, then lower the heat and let it simmer for another 20 minutes.

Blend the soup: Use a stick blender to blend all the ingredients until silky-smooth.

Garnish and enjoy: Transfer the soup to a serving bowl, and sprinkle some scallions and the remaining cheddar cheese. Serve with slices of baguette.