Transfer time from Malpensa to Milano Central

So you already have the train ticket purchased?
IF you land on time, and IF you don't have some horrible line at immigration, you should be OK.
You will need to be on the 10:13 train to Milano Centrale, which will get you there by 11:05 with plenty of time for your 11:23 EC train to Bern.
So if you can get off the plane, through immigration and get your luggage and into the main terminal by 9:45 you'll be alright. It will take about 15 minutes to follow the train icon signs to the airport train station and buy your Malpensa Express ticket.

You should be able to make the connection, but if there are any "glitches" such as a late flight arrival, long lines at Passport control or whatever, it could be tight. Keep in mind also that the trip from MXP to Milano Centrale will take ~52 minutes, so that has to be included too.

The Malpensa Express train to Milano C.le takes 52 min, but you must add the time you might have to wait for the train, since it departs from the airport every 30 min. So potentially it could be 1.5 hours from the time you are at the airport station and the time you pull into Milano Centrale.
That means that you are counting to deplane, clear passport control, retrieve baggage, and walk to the airport station (across the terminal) in less than 1.5 hours. Doable, but flights are sometimes delayed, therefore I never recommend to pre-purchase train tickets on the day of flight arrival.

I always take the bus rather than train from MXP to Centrale. Bus stop is immediately outside the terminals, cost is 8 euro one way (less if purchasing round trip), departure times are posted, and arrival at Centrale makes for an easy trek to the train tracks. Last week I had a train reservation for 3 hours after landing - plane was on time, easy process getting thru customs, but airline lost my luggage, which required extensive paperwork. I made it via bus to Centrale with two minutes to spare for what would otherwise have been a leisurely connection. But, with the super economy fare of 9 euro for a four hour journey to Pesaro, advance purchase was the best option. Travel time by bus to Centrale is about an hour.