Q Can a bakery bake cakes or cookies in the shape of non-Jewish religious symbols  (like a cross) for orders they receive from non-Jewish customers?
A. On question 1650 and 1654 in regard to reciting tehilim when facing a cross in an adjoining cemetery or kidush levana on the street, since all Ontario vehicle plates have a cross on them; we wrote: “Remoh (Y.D. 141,1) prescribes that a cross, worn on a necklace and used as a symbol and not as an object of direct worship is permitted (in benefit). Many Poskim allow the use of coins, stamps or utensils that have a cross on them, since they are used only as a decoration. (Shach ibid., Chochmas Odom 85,1, see also Igrois Moishe Y.D. 1,69 in regards to a medallion or an award). Some Poiskim advise to take off or erase part of the cross.(ibid.). The above would apply to car plates too.
Horav Shlomo Miller’s Shlit”a opinion is that even if they are permitted in use, one should preferably not have them around in one’s home, especially not on the candlesticks of the Shabbos table.”
See also question 1116 in regards to melting a gold cross to make a tzion: “Horav Shlomo Miller’s Shlit’a opinion is that if the cross was seen and served as an idol itself and was worshiped as such, it would become prohibited in benefit. However, if it was only a symbolic object, representing another deity, it would be permitted.”
We may also add that Noda Beyehuda (Y.D. 2: 180) also permits using coins that have an image of idolatry stamped in them since they were not made with the intention of serving avoda zara and it is the hand of the coin stamper that matters. It is unlikely that the workman who presses the buttons when stamping coins or license plates, has any relevant thoughts involved. Similarly Igros Moshe (Y.D. 1: 69 quoted above) permits the use and commercialization of stamps that have an imprinted cross on them, quoting Tosafos (Shabbos 149) that it is permitted when the intention is only for decorating. He also cites Tosafos (Avoda Zara 50) that provides another reason to be lenient on coins, since one is accustomed to the constant use of them. He adds a third reason for the permitted use of those stamps and coins, namely the use itself is not honorific or respectful as they thrown or placed in unclean places.
Although, some Gedolim and Tzadikim, would abstain from using those coins and stamps as mentioned in Tosaffos (ibid.), Orchos Rabbenu (Hosafos p. 3) in regards to the Steipler Gaon zt’l abstaining from the use of some Swiss currency, and others, it was a mainly personal chumra and stringency of the “Bnom shel Kedoshim,” or Holy people. (See also Shoel Umeshiv 1: 3: 71, Minchas Elozor 1: 27 and others)
Horav Shlomo Miller’s Shlit’a opinion is that it is permitted to daven or recite brochos facing a car with Ontario license plates as not only all the above mentioned conditions in Igrois Moshe apply, it may not even posses the form of a proper cross.”
See also question 1050 regarding the many sources and reasons for the minhag of baking a chalah for the Shabbos after Pesach and placing a key inside that chalah, (shilsel chalah). We mentioned that during Pesach we become totally separated from the rest of the nations by the extraordinary prohibition of not eating and owning chometz. After Pesach, we regain permissibility and there is risk of unacceptable intermingling with them and their “chometz”, so we need a key, not to open but rather to close.
The above gains value when we consider how much has been written in regards to the possible (but unlikely) correlation of this tradition with the Christian Easter Breads manufactured in the form of a key and a cross. On Easter, the Christian holiday which celebrates the idea of resurrection, the key shaped like a cross is placed inside a rising loaf.”

In our case Horav Shlomo Miller’s Shlit’a opinion is that one should avoid baking cakes or cookies in the shape of non-Jewish religious symbols  (like a cross) for orders they receive