Typescript jest Expect executes before timed async functions finish awaits

Question

My problem is that I have polling service, which has Begin() and Halt() methods, that starts or stops an interval, via setInterval

Here's a simplified model that replicated the problem as it is.

class IntervalTestCandidate{

    public Data: string[] = new Array();

    private handle: NodeJS.Timer;

    private async component(){
        console.log('something');
    }

    private async obtainData(): Promise<string[]>{
        await this.component(); //If this line is commented out things work as they should
        return ["hello", "world"];
    }

    private async poll(){
        console.log("this is executed");

        let data = await this.obtainData();
        data.forEach(s => this.Data.push(s));
    }

    public Begin(){
        if(!this.handle)
            this.handle = setInterval(this.poll.bind(this), 1000);
    }

    public Halt(){
        if(this.handle){
            clearInterval(this.handle);
            this.handle = null;
        }
    }

}

jest.useFakeTimers();
it('Test Polling', async () => {
    let cand = new IntervalTestCandidate();
    cand.Begin();
    jest.advanceTimersByTime(1001); 
    await Promise.resolve(); 
    expect(cand.Data.length).toBe(2);
});

It seems to have to do with the nested await, So there can be awaits in poll() but if those awaited methods in turn have awaits, it does not work. What I do not understand is why, and if there is a way that I can fix this somehow.

Small Update: After kicking it around for a bit i found out that adding two extra await Promise.resolve() before the expect makes it work. I wouldn't consider this a fix though. Does it have to do with how it switches between Promisejobs?

jest.useFakeTimers();
it('Test Polling', async () => {
    let cand = new IntervalTestCandidate();
    cand.Begin();
    jest.advanceTimersByTime(1001); 
    await Promise.resolve(); 
    await Promise.resolve(); 
    await Promise.resolve(); 
    expect(cand.Data.length).toBe(2);
});

I have done a lot of googling/DuckDuckGoing, but without any luck. Can someone tell me what the problem is, and show me how to do this properly?