Depending on how hot your tap water is, you can often just crank up the hot water and it will be enough. Check with an instant thermometer if you have one. You can also heat up some water in the microwave (its 40 seconds on my microwave, but they all vary). Pour the water in your mixing bowl, preferably a standing mixer with the dough hook.
Add the yeast and give a slight mix. It may seems like a lot, but you also don't have to let it rise like regular bread and helps make it light and airy.
Add the sugar and oil. Let it rest for about 5-10 minutes to be sure the yeast is active - forms a slight brown foam on top.
Add in the flour. And salt. Start the mixer on low, and add in the egg. I prefer cracking into a small bowl just to be sure I don't get any eggshells included - a giant pain to fish out of the dough. Mix on low to medium low for about 5 minutes until smooth and elastic looking.
Turn out on a lightly floured surface and form into a rectangle. Really any size will do, you are just trying to make it easy to get roughly equal-sized pieces. This recipe will make about 8 Texas-sized buns, about 10-12 normal buns, and about 12-16 slider-sized buns. Whatever size you are aiming for, try to keep them as close to the same size for consistent baking. My favorite dividing tool is my bench scraper. Cut the rectangle in half, then each half in half, then turn your scraper 90° and cut the four pieces in half. On your surface or hands, roll into balls and place on a sheet pan that has been lightly greased or has a Silpat or parchment paper. Try to space them out evenly so they have room to spread, but don't fret about them touching, it makes it look like they were store-bought if they do.
Cover (I prefer some clear plastic wrap that has been lightly oiled), and let rest for 10-15 minutes. Heat oven to 425°.
I like to flatten them down a bit in the center. The primary reason is so you don't have giant orb-like buns, but I find it also allows them to brown a bit more evenly. Bake for about 10-15 minutes. I start checking them at about 8 minutes, but they are usually done around the about 12 minutes, and 15 minutes if you like them a little more brown. When done, transfer them to a wire rack to rest and cool for about 10 minutes.