This is an excellent base recipe for muffins. I made mine in a jumbo tin and they turned out very moist and kept well for several days. Next time I will not add pear however as I felt it was a strange combo with the raspberries. Will make these again with very few alterations

I baked these at 6500' and adjusted the recipe accordingly.
This is a VERY moist muffin. I had to bake them for 35 minutes. Do Not Be In A Hurry to remove them from the tin. WAIT at least the recommended 15 minutes or more.
It's worth the wait they a very good.
Truely a Rouxbe trophy.
I wouldn't change a think except to accomplish a great muffin.

Could you use frozen berries in this recipe? Would you have to modify anything else to make the recipe work?

Frozen berries would work. Fold them in while they are still frozen (don't thaw them). If you are using just frozen berries and no pear, I would use a bit less - maybe 1 cup total berries. Cheers!

How long is baking time for mini muffins ? If i substitute all pear with fresh raspberries should i use the same amount?

Thank you

It will depend on the size and the actual internal temperature of your oven. Keep an eye on them and check near the 10 minute mark. Cheers!