Ancho Chile and Chile de Arbol Powder
Could anyone tell me where I might find these chile powders in the Needham, Newton, Wellesley areas? Whole Foods, Sudbury Farms, Trader Joes?
Not in those towns, but in Arlington and via mail order -- Penzey's Spices definitely has the Ancho chile powder. Don't know about the other.
As the other poster said, Penzey's should have both at either the retail store in Arlington or via mail order.
I have also purchased both of these at Christina's Spice in Cambridge. I realize these are both a little out of your range.
Christina's Spice & Spec Foods
1255 Cambridge St, Cambridge, MA 02139
Many Latin markets (and Super 88) should carry the whole peppers. I like to buy it that way and use a spice grinder to make the powder.
Not really familiar with the areas you mention and can't offer specifics.