The house is already constructed and stucco is done.  The homeowner wants to add a covered entry porch.  What is the best way to attach beams and ledgers to the icf?

Cut down to the concrete face and use concrete anchors.

Simpson makes what I will call a reverse flange hanger, the flanges are to the inside of the hanger.

Carefully layout and remove the stucco and ICF to the concrete as tight as possible. If you are careful you will not have to re-stucco the wall

Insert and secure hangers with supplied screws, set beams and your done.

Thank you. This is what I figured I would have to do, but the builder is balking.

Use standard wedge or epoxy type anchors into the concrete. Remove 2x2 of foam around the anchor and slide a piece of 2x2x.25 tubing (the depth of the icf) over the anchor. Seal tubing to stucco with sealant. Install ledger and tighten anchors to force the ledger into contact with the tubing. Alternate the anchors up and down to keep ledger in plane.