Just one example of many: Big Bang theory accurately predicts the relative abundance of the elements hydrogen and helium. Evidence for this is obtained at the high energies achieved in particle accelerators such as Fermilab. I saw such experiments first hand when I took some physics classes there in the 1980’s.
Google “Quantum Electrodynamics” to find more examples.
The relative abundance of hydrogen/helium was well known before the Big Bang theory was formulated so how is predicting that which is already known meaningful? And it didn’t require a particle accelerator to find this out.