Here's a little one-shot based on my AU story, "John on Solid Ground." I'm working on the plot to a chaptered sequel now, but I'm going to write a few of these little slice-of-life one-shots based on "Solid Ground" at the same time.

Beta'd by Teek. Britpicked by johnsarmylady. Many thanks! And also thanks to johnsarmylady for giving a name to this series: the Mountainverse.

To WhiteRookBlackBishop, who claims to like such caring things.

This story comes from the following situation in Chapter 8:
John turned into quite a good cook while experimenting around with recipes that would pack the necessary weight onto the mountaineer in time for the expedition. Sherlock's shirts, skin-tight from the beginning, almost immediately started straining against his chest, and he went up a size within a short time of John moving in. Sherlock admitted to John that this was the easiest he'd ever found it to gain weight before a climb, though he did not admit how thrilled he was to have John cooking and caring for him. That would be sentiment. But he figured John knew anyway. Somehow, John always knew.

JUST DESSERTS

John Watson stood in the kitchen of 221B Baker Street trying to decide what nourishing meal to prepare next to put a little more meat on his flatmate's bones. Sherlock Holmes was going to need to bulk up by at least twenty-five pounds in the four and a half months leading up to his next trip to Everest, because he was probably going to lose that much during the expedition. Certainly he currently had no weight to spare — the mountaineer worked out so strenuously that he usually ended up running a calorie deficit no matter how hard he tried to gain weight.

Sherlock wasn't a picky eater but it was a source of pride to John to make the meals not only nutritious, but also delicious. He wasn't sure exactly when he had started thinking like a home economics teacher, but he had taken it upon himself to try to pack sorely-needed pounds onto the slender mountaineer only two days after he moved into Sherlock's bedroom.

They had now been living together about two weeks.

"Jawn! Jaaaaawn! Look! My shirt doesn't fasten!" Sherlock came bursting into the kitchen, grabbed John and waltzed him around in delight for a few beats. His shirt was unbuttoned. His body radiated heat.

John's pupils dilated and he pressed several kisses to Sherlock's prominent collar bones. "How is that any different than usual?" he asked with a bit of a smirk. Sherlock normally wore his shirts skin-tight, and his buttons continually threatened to pop off whenever he took a deep breath.

"Ha ha," responded Sherlock drily, snagging John by the belt. "Come with me and let's pick out what size I should go to next."

As if Sherlock couldn't do that himself. But any old excuse to end up in the bedroom! John smiled and allowed himself to be tugged along.

Probably no one but Sherlock would find growing out of his "skinny clothes" to be a happy event under normal circumstances. But in this case, it did deserve a bit of a cheer. Sherlock needed to gain weight and clearly he had already put on at least five pounds, which was all it would take for him to outgrow those form-fitting shirts of his.

Sherlock threw open the closet with a dramatic flourish and started pushing his smaller shirts aside. Because of his yearly weight fluctuations, he bought every item of his clothing in three sizes. He was wearing the largest size by the time he was ready to leave for the expedition and the smallest size was there, ready for him to slip into when he got back from Everest two months later. It was the middle size he was aiming for now.

As he shoved past the smallest shirts he said, "John, this is the fastest I've ever put on weight before an expedition."

John looked pleased. "I'm glad I could help."

"More than just help," Sherlock insisted. "I've never been able to gain the weight this easily before."

"Good, because to be honest, so far I've felt like my entire 'contribution' to the expedition has been to turn one of the world's premier climbers into an instructor for a private course on remedial mountaineering."

"John, I already explained to you that even if you never venture one step beyond Base Camp, I want to be sure you know some climbing fundamentals. I'm very relieved that your surgery let you go early, and we have that much more time to prepare."

"Let me go early?" John snorted. "What a very polite way of saying they couldn't rush me out of there fast enough."

"Their loss is our gain," Sherlock said smugly. He pulled out the next size up of the exact shirt he hadn't been able to button and tried it on. He frowned when he realised it was a little bit loose: no gaps at all between the buttons; no straining at the chest. He had come to rather enjoy the look of desire on John's face when the doctor watched him buttoning (or unbuttoning) his skin-tight shirts.

Suddenly John said, "In any case, maybe you should start wearing less-revealing clothes now that we're together." Then he winced, realising how ridiculously proprietary that must have sounded when he hadn't really meant it that way…well, not exactly. Probably not, anyway.

Sherlock smirked, somewhat aroused by the display of possessiveness. He strutted up to John until they were face to face…or more accurately, neck to face. "Are you jealous when others look at me?" he murmured into John's ear, lowering his voice seductively.

"A bit, yeah," John admitted sheepishly to Sherlock's neck. "I mean, would you really like it if I ran around flaunting myself?"

"What?" Sherlock slipped his hands into John's back pockets and pulled their bodies flush together at the hips. "You don't think you run around looking good enough to eat?"

"Frankly, no," John said, nibbling at Sherlock's jaw. He had yet to figure out what his flatmate saw in him. Short, stocky, nowhere near up to Sherlock's brilliance, and apparently a target for the fashion police on top of everything else. "I know you hate my clothes."

Sherlock actually loved John's clothes; loved the way every dull, boring stitch came together to make John look totally adorable. The wrinkled jeans a little bit too long for him. His ridiculously unfashionable jumpers, most especially that black-and-white striped thing that taunted Sherlock to peel it off every time John donned it. Even that corduroy monstrosity John called a suit looked delicious on him.

But there was no way Sherlock was going to admit to any of that. "I don't hate what's under them," he said with a smirk. He tugged at the hem of John's jumper. "But you did such a good job feeding me up…and I did such a good job gaining weight…I think it's time for our just desserts now." He pulled John's jumper up and off and started unbuttoning the shirt underneath.

John pretended to misunderstand. "What? But we haven't even had lunch yet!"

"You know very well that I am not talking about food," Sherlock said huskily, crowding John towards the bed with a very determined look on his face. In a couple of steps he had John down on the duvet and they laughed happily together as they stripped each other bare.

I actually do know (as would Sherlock) that the original expression is spelled "just deserts"…but that would only be confusing in this context, so…sorry, accuracy! You're out the window.