10NL online full ring
Hero: $10, QQ HJ
UTG: $19.88 unknown
LJ: $17.56 unknown

Preflop
UTG opens to $0.20, LJ raises to $0.60, Hero calls, UTG calls

My thinking: It looks like I'm against two pretty damn strong ranges, so I don't think I want to raise. I have position, deep stacked with a strong hand, so I don't think I want to fold.

I'm not sure though. Maybe folding is right. What am I doing here? Set mining? I guess it's a solid spot for that given how deep stacked we are and that I could win a lot versus AA or KK. I don't really see what other good can happen. Maybe calling an AK bluff with QQ overpair, or getting to showdown versus two weaker pocket pairs, but that doesn't sound too +EV.

Flop ($1.85)
AA5
UTG bets $1.95, CO calls, Hero ???

My thinking: What worse hands could be betting and calling? Weaker pocket pairs? Weaker pocket pairs can't really justify betting for value. And betting as a bluff doesn't really make sense multiway versus strength. Plus, even if you are going to bluff, makes sense to use pocket pairs as showdown value hands and use a different part of your range to bluff.

Even with two aces on the board, there's still one combo of AA, two of AKs, six of AKo, plus probably some AQs and KK.

Standard call pre.
Standard fold flop vs 2 players. His big donk seems super strong.

@Streptocoque

Would you mind elaborating on where you see the value coming from with QQ (set mining, overpairs, etc.)?

You need to think about the opponent's range. He's probably not flatting the 3bet with AA/KK only. His range could be way looser. In fact, your flat call behind gives him the odds to call with all his pocket pairs + some suited connectors + AK, at least. And I assume he's often 4-betting with AA/KK here (this doesn't means he's never flatting with those hands).
Folding is out of question. You have a strong hand, which is under represented. You have the odds to setmine if LJ has a better starting hand. And you can always choose to fold if UTG shoves or 4bets big and LJ calls.

So you're not only setmining, you are playing with positionnal advantage. Position is information. You can evaluate the relative strenght of your hand depending on the texture of the board and the action of your opponents. This flop is obviously super bad for you, especially against his overbet. Personnaly, if I was villain, I wouldn't donk on this board, even with AK, because it allows you to cheaply get out of the hand. But really, I don't see him betting with worse than your QQ against 2 players who have many aces in their ranges.

But let's say the board comes 752o. Here you would have a strong overpair which is really hard to fold. You can't totally discount AA/KK in the opponents ranges, but they could bet smaller overpairs for value (JJ/TT/99/88). UTG has also some sets here. So in this case, I would advice flatting flop and reevaluate turn. It's a classic way ahead/way behind spot.

@Streptocoque I agree that there's value to be had from UTG, but LJ is the one that really worries me, because I have a hard time imagining someone three betting an UTG open with much that I beat. AK and QQ could be three betting the UTG open, but JJ? TT? 99? AQ? AJ? I get the sense that those hands would flat, and so I'm not seeing much value with QQ other than as a setmine. Do you agree with that, or are you seeing other value against LJ?

Well, I think you are overestimating the value range of the unknown LJ. He could also use a polarized 3bet range, with some suited connectors, some suited wheel aces, and maybe some offsuit mid-kicker aces which are not strong enough to play as a call. It works, because your percieved range seems super strong when you 3bet an UTG open. But I agree that mid and small pocket pairs (under JJ) will be mostly played as a flat call.

Good point about Villain possibly using a polarized 3bet range, and that I beat the bluffing part of that range.

Where I'm mainly coming from I think is that I assume that players at NL10 are very passive and value heavy. That's the big reason why I'm assuming the 3better is so strong.

This is 10 nl, which means a few things:

1) UTG min raised from UTG... at 10 nl this is never a good player being fancy and is almost always a bad player. Enough info to act on in fact that he is a bad player, and the flat pre also confirms that.
2) LJ's 3bet pre isn't nearly as strong as you think. It's a <1 psb in a still small pot. I think LJ can definitely have an KQo ATs type hand in addition to any suited ace.
3) Anyone paying attention knows you have 99-QQ and AQ/AK. They're the only good hands a regish player like yourself flats to a 3bet at this level. Despite this vill donks a psb in a 3 player 3bet pot.

Conclusion:
Easy fold if you think UTG is a good player who raised min pre. However I think this is a bad player. Unfortunately without knowing more about vil i think this is a fold on the flop.

EDIT: Just noticed CO called. Easiest fold of my life - one of them (or both) has an A. On top of that a non-zero amount of the time you hit your Q but still lose his stack to his A hitting a full house (a Q turn 5 river and you lose to any A on the AA55Q board)

@Searix

Thanks for that input! That's an interesting point about reading in to the minraise from UTG.