• Place an oven rack in the center of the oven and preheat the oven to 425°F. Scrub the potatoes clean and dry them thoroughly. Pierce each potato several times with a fork or the tip of a knife. Rub the skins with avocado oil and sprinkle them generously with kosher salt.
• Place the potatoes directly on the oven rack or on a rimmed baking sheet. Bake for 50–60 minutes, until they give easily when gently squeezed and a knife slides into the centers without resistance.
• Remove the potatoes from the oven and let them cool just until they can be handled comfortably. The potatoes should still be warm when you make the filling. Reduce the oven temperature to 350°F.
• Decide whether you want two smaller portions or one large stuffed potato from each russet. For two smaller portions, cut the potato in half lengthwise. This creates two potato boats and works especially well when serving the potatoes as a side dish. For one large portion, place the potato on its most stable side and slice a thin section from the top. This leaves the main potato intact and creates one generously filled potato.
• Hold the warm potato with a clean kitchen towel if needed. Use a spoon to carefully scoop the flesh from the shell and transfer it to a bowl. Leave about ¼ inch of potato around the sides and bottom so the skin does not tear and the shell remains sturdy enough to hold the filling. If using the whole-potato method, scoop the potato flesh from the removed top into the bowl as well. Save the empty top to make a small potato skin, if desired.
• Add the butter to the warm potato flesh and mash until the butter is melted and incorporated. Add the sour cream, cheddar, bacon, green onion, salt, and pepper. Gently mash and stir just until combined. Do not whip or overmix the potatoes, which can make the filling gummy. Taste and adjust the seasoning as needed.
• Arrange the empty potato shells on a rimmed baking sheet before filling them. Spoon the filling into each shell, piling it gloriously high without pressing or packing it down.
• For a more decorative finish, transfer the filling to a piping bag fitted with a very large open or star tip. The bacon and green onions must be chopped finely so they do not clog the tip. You can also use a large food-storage bag with one corner cut off. Pipe the filling loosely into the potato shells.
• Bake at 350°F for 20–25 minutes, until the filling is hot throughout, lightly puffed, and browned in spots.

Storage

• Store leftover twice-baked potatoes in an airtight container in the refrigerator for up to 4 days.
• Reheat refrigerated potatoes uncovered in a 350°F oven for 20–30 minutes, or until hot throughout. They can go directly from the refrigerator into the oven.
• To freeze, assemble the potatoes but do not bake them a second time. Allow them to cool completely, place them in an airtight freezer-safe container, and freeze. Thaw overnight in the refrigerator, then bake uncovered at 350°F for 20–30 minutes, or until heated through.

Notes

• Russets, also called Idaho potatoes, are the best choice because their high starch content produces a light, fluffy filling and their sturdy skins hold up well when scooped and filled.
• The ingredient amounts are listed for one potato. Multiply each amount by the number of potatoes you want to prepare.
• If using the whole-potato method, the removed top can be topped with a little cheddar and bacon and baked alongside the filled potato to make a small potato skin.