Start by roasting the sweet potatoes. Preheat your oven to 400°F (200°C). Pierce the sweet potatoes with a fork and place them on a baking sheet. Roast for about 45-50 minutes, or until a knife can easily slide through the flesh. Let them cool, then peel and mash until smooth. I've found that roasting, rather than boiling, deepens their natural sweetness and prevents excess moisture, which could affect the dough's consistency.

In a large bowl, combine the warm milk, melted butter, sugar, and yeast. Stir gently and let it sit for about 5-10 minutes, until the mixture becomes frothy. This is proofing the yeast, and it's crucial for the rise of your rolls. In my early attempts, I rushed this step and ended up with flat rolls, so patience here is key.

Add 1 cup of mashed sweet potato and the egg to the yeast mixture and mix well. Gradually add 3 cups of flour and salt, stirring until a sticky dough forms. If the dough is too wet, add more flour, 1 tablespoon at a time, until it comes together. I've learned that the dough should be tacky but not overly sticky, which is the secret to light and airy rolls.

Turn the dough out onto a floured surface and knead for about 8-10 minutes, until it's smooth and elastic. This kneading process is therapeutic, but also essential for developing the gluten, which gives the rolls their structure. In my first few tries, I under-kneaded, resulting in rolls that lacked volume.

Place the dough in a greased bowl, cover with a damp cloth, and let it rise in a warm place for about 1 hour, or until doubled in size. I've found that a slightly warmed oven (turned off after preheating for a minute) provides the perfect environment for this first rise.

Once the dough has risen, punch it down to release the air. Divide the dough into 12 equal pieces and shape each into a ball. Place them in a greased 9x13-inch baking dish. Cover and let them rise again for about 30 minutes, until puffy. This second rise is just as important as the first; it ensures that the rolls bake up tall and fluffy.

Preheat your oven to 375°F (190°C). Bake the rolls for 20-25 minutes, or until they're golden brown on top. If you tap them, they should sound hollow. I once left them in a tad too long, and the bottoms darkened more than I liked. Keep an eye on them as ovens can vary.

Optional: For a sweet, shiny finish, brush the tops of the rolls with a little honey as soon as they come out of the oven. This step, suggested by a baker friend, adds a lovely sheen and a touch of sweetness that complements the sweet potato flavor beautifully.