Is mole spicy?
It can be, but it does not have to be. For a milder mole, remove seeds and stems from the dried chiles and use more ancho and pasilla with fewer chipotles. You should taste warmth, not regret.
Quick heat guide: 1 chipotle is mild-medium and smoky. 2 chipotles is medium with a noticeable kick. If you are heat-sensitive, start with 1 and add more adobo sauce at the end.
Does mole always have chocolate?
Not always, but many classic moles do. The chocolate is not there to make it taste like dessert. It adds roasty cocoa depth and helps round the edges. Mexican chocolate is usually sweetened (and sometimes lightly spiced), so it can add sweetness too. Bittersweet chocolate tastes darker and less sweet. Use what you have, then balance with sugar and salt to taste.
What chiles should I buy?
Look for ancho (mild, raisiny), pasilla (earthy), and chipotle (smoky heat). If you can only find two, ancho plus chipotle will still get you somewhere delicious.
Chile swap note: If you cannot find pasilla, mulato is the closest vibe. Guajillo also works in a pinch, but it is brighter and a little tangier than pasilla, so your mole will taste slightly lighter and more red-fruity.
Why is my mole bitter?
The usual culprit is over-toasting the chiles or spices. Toast until fragrant, not until black. If it is already a little bitter, you can balance it with a touch more sugar and a bit more chocolate, then simmer 10 minutes.
If the chiles were truly scorched, the bitterness may not fully disappear. Your best rescue move is to strain the sauce (to remove any tough bits), then loosen with a little extra broth and rebalance with salt, sugar, and chocolate. Prevention is still the real hero here.
How do I fix a mole that is too thick?
Whisk in warm chicken broth a little at a time until it is glossy and spoonable. Mole should coat the back of a spoon, not sit in the pot like wet cement.
Can I make this in advance?
Yes. Mole is even better the next day. Make the sauce, chill it, then rewarm gently and simmer the chicken in it when you are ready to eat.