Your statement that Allah created evil is not correct. Misguided people perform 'evil' actions, or say 'evil' statements. They do evil when they are not Allah conscious when they conduct themselves. The constant temptations and whispers by Sheythan does not help. They need to be Allah conscious as they conduct themselves throughout the day. This is known as 'Taqwa' and it is emphasized repeatedly throughout the Quran. Just one sample:
Yā 'Ayyuhā Al-Ladhīna 'Āmanū Attaqū Allaha Wa Ltanžur Nafsun Mā Qaddamat Lighadin ۖ Wa Attaqū Allaha ۚ 'Inna Allāha Khabīrun Bimā Ta`malūna
O ye who believe! Fear God, and let every soul look to what (provision) He has sent forth for the morrow. Yea, fear God: for God is well-acquainted with (all) that ye do.
يَاأَيُّهَا الَّذِينَ آمَنُوا اتَّقُوا اللَّهَ وَلْتَنْظُرْ نَفْسٌ مَا قَدَّمَتْ لِغَدٍ وَاتَّقُوا ۖ اللَّهَ إِنَّ ۚ اللَّهَ خَبِيرٌ بِمَا تَعْمَلُونَ
Wa Lā Takūnū Kālladhīna Nasū Allaha Fa'ansāhum 'Anfusahum ۚ 'Ūlā'ika Humu Al-Fāsiqūna
And be ye not like those who forgot God; and He made them forget their own souls! Such are the rebellious transgressors!
وَلاَ تَكُونُوا كَالَّذِينَ نَسُوا اللَّهَ فَأَنْسَاهُمْ أَنْفُسَهُمْ ۚ أُوْلَائِكَ هُمُ الْفَاسِقُونَ
The practice of the 5 daily salat, zekat (charity), and sawm (fasting) help to enforce taqwa.
Allah is the most beneficent (Al Rahman), the most merciful (Al Raheem), the most good, and the source of goodness.
Another way to define evil:
There is no real such thing as darkness. It is simply the absence of photons (electromagnetic waves/particles) of visible wavelength. Allah created light. Darkness is the absence of light.
There is no real such thing as cold. It is simply the absence of heat (thermal energy of photons in the infrared wavelengths emitted by molecules in motion). Allah created heat. Cold is the absence of heat.
There is no real such thing as silence. It is simply the absence of sound (mechanical vibrations in air and other matter). Allah created sound. Silence is the absence of sound.
So, there is no real such thing as 'evil'. It is simply the possible resulting conduct of people who are not practicing taqwa. Allah created good. Evil is the absence of good.