The Stefan Müller Winery is located at the entrance to Krettnach, in the middle of the so-called "Konzer Tälchen" (Konz Valley). In this former meander valley of the Mosel (yes, the Mosel, because the confluence of the Saar with the Mosel near Konz is only a stone's throw away), wine has been cultivated for over 2,000 years. The local winemakers have experienced many ups and downs during this time. In the 1960s and 70s, the valley experienced a real boom. Cheap mass-produced wines were produced on a large scale here in the relatively flat vineyards for Saar standards. However, wine production here was like riding a razor's edge, because due to its rather high altitude, the valley has always had a comparatively cool climate. What proves to be extremely useful today in times of climate change was then a big problem, because many vineyards were extremely susceptible to frost and, in many years, the grapes simply did not ripen at all. Today, however, the Saar in general and the Konzer Tälchen in particular are two of the few wine-growing regions that benefit enormously from climate change. The grapes ripen perfectly year after year, and due to the still comparatively cooler climate, cool-tasting Rieslings can be produced here in the Konzer Tälchen even in hot years like 2015 or 2018. In addition to the blue Devonian slate soils typical of the Saar, there is also a special feature here. Especially in the vineyards around Krettnach, such as in Altenberg and Euchariusberg, a volcanic rock called diabase is increasingly found, a special feature that otherwise only occurs in such quantities in Saarburger Rausch.

In 2012, at just mid-20s, young winemaker Stefan Müller took over his parents' winery after several internships abroad in Europe and overseas. He turned everything upside down: flat parcels were, wherever possible, exchanged for steep slopes in the mountains; yields were massively reduced; manual harvesting and meticulous selection in the vineyard have since become the method of choice; and from then on, all herbicides and industrially produced fertilizers were eliminated. Today, Stefan Müller focuses on the most natural cultivation of his vineyards. By using natural fertilizers and plant fortifiers, he aims to strengthen the natural biodiversity in the vineyard and the vines' natural defenses, thus minimizing the need for plant protection measures. Furthermore, he rediscovered traditional winemaking methods in the cellar. First, he gradually bought back traditional oak fuder casks that had been replaced by modern stainless steel tanks years ago. And with his very first vintage in 2013, Stefan Müller banished all "winemaking aids" such as cultured yeasts and fermentation aids from the cellar, utilizing the potential of natural yeasts (the so-called spontaneous fermentation process) and, together with his wife Johanna, produced the first wine of the new winery named TANDEM. The label features a tandem bicycle, symbolizing the collaboration between Stefan Müller, a trained viticultural technician, and his wife, sommelier Johanna Lapinksi. It is a juicy, off-dry quality wine that clearly defines the style of the house.

By foregoing skin contact and using whole-bunch pressing – meaning the direct processing of completely intact berries after harvesting – Weingut Stefan Müller produces precise and unembellished Rieslings with bell-clear fruit. The wines are consistently elegant beyond measure, always have extremely low alcohol content, possess enormous aging potential, and are exceptionally affordable to boot. This unique combination has not escaped the notice of the Republic's major wine guides, such as Gault & Millau and Vinum. After Stefan Müller was awarded the title "Saar Young Winemaker of the Year" by a regional expert jury in 2016, the ultimate accolade followed in 2017: Gault & Millau Discovery of the Year 2018. With this prestigious award, he finds himself in prominent company on the Saar, as previously this title had only been bestowed upon the top winery Van Volxem in 2002. In recent editions of the major wine guides, numerous Stefan Müller wines have been highlighted as wines offering the best value for money. Today, as a third-generation winemaker, he cultivates just over 10 hectares of vineyards, primarily growing Riesling (80%), but also Pinot Blanc and Pinot Noir, in the top sites of Krettnacher Euchariusberg, Krettnacher Altenberg, Niedermenniger Sonnenberg, and Niedermenniger Herrenberg. Furthermore, in 2017, Weingut Stefan Müller was an early "SAARKIND." This burgeoning association of 10 young winemakers is currently causing quite a stir and aims to contribute to the attractiveness of the Saar-Obermosel region with innovative campaigns and events.