So the rules read:
Gold bordered skill icons are SPECIALIZED. If a soldier is assigned to a specialized skill icon and has a matching specialized skill icon on its reserve card, the Squad Lear rolls one additional XCOM dice during the resolution of the task.

My question, do I just add one dice no matter what to the resolution, or do I add one dice per specialized matching skill?

For example: I'm resolving Sectoid Commander which has a Positioning, Critical, and Teamwork icons on it. I have a Sniper, a Support, and an Assault assigned to this. Do I roll 4 dice? (3 per trooper + 1 for having a specialized icon) Or do I roll 6 dice ? (3 per trooper + 1 additional dice per matched specialized icon)

You need to match Gold-Border to Gold-Border. If only the Soldier has the gold border and the task/alien does not, you do not add a die.

If a Sectoid Commander had 3 different Gold-Border icons and you threw at it 3 soldiers who matched 1 or more Gold-Border with their own Gold-Border, then yes, you would roll 6 XCOM dice vs. 1 alien die. (2 dice from each solider since they each have a matching Gold-Border skill)

I'm not sure if you accounted for this or not, but here's how you assign soldiers and figure out the dice, using your

My question, do I just add one dice no matter what to the resolution, or do I add one dice per specialized matching skill?

For example: I'm resolving Sectoid Commander which has a Positioning, Critical, and Teamwork icons on it. I have a Sniper, a Support, and an Assault assigned to this. Do I roll 4 dice? (3 per trooper + 1 for having a specialized icon) Or do I roll 6 dice ? (3 per trooper + 1 additional dice per matched specialized icon)

I'll use your example with that Sectoid Commander and I hope this helps;

The monster has Positioning, Critical and Teamwork icons

You can assign 1 soldier to each icon, for a maximum of 3 soldiers attacking the monster

You chose a Sniper (gold Critical), Support (gold Teamwork) and an Assault (gold Positioning)

So here's how you would add up how many dice you're rolling;

• 1 die for each soldier assigned to an icon; in this case it is 3 dice
• 1 die for each matching specialized icon; if the soldier has the same gold icon as the monster, add a die
• 1 die for each elite soldier assigned to an icon

You would only be rolling 6 dice in your scenario IF each icon on the monster card was also gold. So looking at the two Sectoid Commander cards I have in the game, all icons are white, with no specialized icons, therefore, unless you had an elite soldier, you would only be rolling 3 dice in practice.