SARS CoV-2 vaccines, which deliver full-length S either as mRNA or as recombinant protein have saved over 20 million lives since their roll out. However, the periodic emergence of global variants has necessitated the updating of vaccines to maintain effectiveness against the new viral strains. The S protein-based vaccine that is currently licensed for human use is produced by a complex process that reconstitutes S in an adjuvanted nanoparticle. The advent of a simple method for producing stable soluble S trimers that can be stored and distributed without the need of an ultracold chain would fill a significant gap in the current arsenal of COVID-19 vaccines. The aim of this study was to produce an intrinsically stable soluble S trimer with improved antigenic characteristics. This was achieved by first modifying the stem/HR2 region of a soluble, trimeric prefusion-stabilized omicron BA.4 glycoprotein containing the core-filling mutations, A1016V/A1020I, to increase the yield of trimer. The thermostability of the stem-modified glycoprotein was then increased by the introduction of artificial intermolecular disulfide bonds between subdomain 1 and heptad repeat region 1 of the spike. Neutralizing antibody epitopes involving the receptor-binding motif (RBM) were occluded to varying extents by the engineered disulfides, whereas conserved NAb epitopes located on the flanks of the RBD remained exposed, and a conserved neutralization epitope within the stem was stabilized by the mutations. Similar results were obtained with the omicron BA.2.86 spike. The intrinsically stable soluble trimeric S glycoproteins represent novel vaccine candidates in which variable epitopes overlapping the RBM can be occluded to potentially redirect antibody responses to more conserved regions of S.